The unique 68 vette – or why won’t that later c3 part fit

If you ever become the owner of a 1968 Corvette you will quickly come to realise that GM did things a bit differently with this car when it comes to parts.  Sure, as the first of the C3 generation of vettes you could expect it to not share a lot with it’s predecessors (although it did still share a chassis and certain other drivetrain components).  However what you may not expect is how many of the parts changed several times within the 68 production run, and how many then were not carried over to the 69 and later years.

What this means is that some original parts that you think might fit, won’t. Some original parts you won’t be able to find easily.  And you will expect to have to pay exhorbitant prices due to either the original parts rarity, or the low volume production/demand for reproduction parts.

Over the past year I have come across a lot of info on the internet about the supposed unique parts on these cars and have been noting them down with the aim of compiling a useful list here.  Some of the links to the original source of the info I have lost, or just do not work anymore, however a lot of the items below have been collated from dozens of posts at http://forums.corvetteforum.com.  Using the search function there will find the source of many of these.

So onto the list.  These are all either parts that are supposedly unique to the 1968 vette, or only shared with perhaps one other model year.  If you can shed any light on whether these are correct or not, post a comment and I will amend the list as needed.  I’ll also be adding pics of any of the various unique items as I come across them. Where I remember I have linked the item to the source info I used for it.

[5 March 2015] Just came across  this site which has a handy illustrates summary of some of the 68 differences.

Last updated 5 March 2015

Interior

  • Left side dash panel with ignition switch
  • Right side dash panel with no map pockets
  • Two different 68 only style interior door panels – door pulls added for later 68’s as the original hidden ones would crack
  • No pull loops on rear compartment doors
  • The coupe interior had 2 sail panel courtesy dome lights (one on each side) that was reduced to just one for 69, (drivers side) and later dropped completly.
  • 2 different types of spring loaded rear compartment hinges
  • Coupe middle storage compartment lamp assembly/lens is possibly unique. Some people have said they have a simple bare lightbulb, not the more normal lamp assembly and cream colored lens
  • Early seats & seat backs are unique to 68 – release lever is on the lower part of the seat back (and is really annoying to get to when the seat is all the way back in the tracks!)
  • Second design seat shared with 69 – release lever on the upper part of the seat back
  • 3 different headliner types for coupes
  • Removable rear window latches – different shape to later models
  • Steering column – under dash mounts differ from later years – cast rather than the later pressed metal design
  • Steering column itself is similar to (but not the same as) the 67 in design and assembly
  • Shifter ball  is a plain chrome ball (not the black chrome as found on 69’s and up)
  • Shifter console plate has no engine ID plate
  • Park brake console – the parking brake console had pockets for the seat belts
  • Seat belts were possibly one year only items
  • Comfort weave seat covers were a 1 year only option
  • Tobacco was a one year interior color option
  • The shift boot on early cars was part year only, later ones were the same as found on 69’s
  • The center gauge bezel has a smooth finish, not the wrinkly finish as on 69 and up
  • Some variations in door ajar lights in the center gauge bezel across the production run
  • Wiper overide warning indicator can be found on the center gauge bezel of some models
  • Radio knobs had 2 different 68 only styles
  • Kick panels were one year only style
  • The panels that attach to the side of the forward console were a part year release –  early car ones just had a clip while later ones had a screw fastener
  • Steering wheel was 16″ simulated wood (may possibly be shared with 67 so some say)
  • Early 68 interior door handles were smooth on the back – later casting had ribbing on the back for added strength
  • Dash mounted ignition switch
  • Windshield pillar interior moldings on inside of car were unique
  • The original external seal between the door windows and the door was unique. It was a strip of rubber about 1/2 inch wide that ran the length of the window – it made a seal between the window and the top of the door. It was completely external as compared to the 1969 window seal that is partially internal. No repro items seem to be available.
  • T-top weatherstrips
  • T-top moldings
  • The center wiper/dash vent bezel on a/c cars was unique.  Reproductions are not available so if you have one spare let me know as I’d love to replace my broken one!
  • Brakelight switch is a square one year only item – the original 68 switch has a toggle type switch (later models used a plunger type) that when you press the pedal the switch closes the circuit and the tail lights come on. When it goes bad what you see is people using the 69 and later switch as a replacement using a different mounting bracket.
  • Early year plastic front fiber optic plate is different
  • Vent knobs carried over into early 69’s but changed thereafter
  • Early 68’s had the vacuum/wiper overide controls more to the right near the console. They were moved to center later in the production run
  • The 68 tach cable was screw on as opposed to the later clip style
  • Tach cable length is different in 69-later cars
  • Headlight switch bezel was unique to 68
  • The turn signal switch in the steering column is shared between 67 and 68 models
  • Only telescoping steering option – no tilt option until 69
  • Real halo panels (on coupes) were configured differently.
  • No gromments were used under the interior dash screws.
  • Shoulder belts did not retract, had a “hanger” and did not have the guides on top of the seats as found on some 69 models
  • Flasher location was changed from center console to pass side dash panel during the production run
  • Brake handle is 68 only
  • Steering column covers
  • Top dash cover has no speaker holes
  • Bracket for drivers side odometer-reset/speed warning/courtesy light is different between early and late 68,  Early has no provision for courtesy light (is possibly separate piece that screws on).  Late bracket is all in one with hole for courtesy light included.
  • Sunvisors/pins were unique to the 68 model and also differed between the coupe and convertible versions.  Also according to the “Corvette Parts Interchange Manual 1968-1982” the part numbers changed in approx Feb 1968.

Exterior/Mechanical/Body

  • Doors had wider door panels – 69 were scalloped to give more room inside the car
  • Exterior door handles
  • Push buttons to open doors
  • Door internal latch mechanism unique to match push buttons
  • Door window wipes inner and outer were of awhisker style, not the felt used later
  • 2 or 3 different windshield header moldings used across production run – early cars were 1 piece design
  • 2 different top alignment pin receivers
  • Outer windshield moldings
  • Removable hardtop rear mounting hardware was different, pin size was smaller, no 3rd center bolt, convertible top rear pin latches different
  • Wheels  were 7″ wide rims
  • Back up/reverse lamps on rear valance/exhaust panel, whcih makes the panel itself different to 69+
  • Gas door emblem riveted on gas tank fill lid
  • Gas door bezel used an interference fit rather than a spring clip to hold it open.
  • Side marker lights were white lenses instead of yellow as in later years.
  • Rear deck vents
  • Antenna mast and nut shared with 67 – but exterior bezel is a 1 year only and not repro’d.
  • Front grilles had several production changes over the years run – chrome/silver paint only on the leading edges of the center 4 ribs across the whole grill, including the center.  Some later 68’s may not have had the silver paint.  Also ribs protruded from surround edge, as opposed to 69/repro where the ribs front is flush with the plastic of the surround.  See this thread for good pics and descriptions – http://forums.corvetteforum.com/c3-general/2983666-1968-grille-pics-needed.html
  • Small front spoiler
  • Front grill brackets made up of multiple pieces – 69’s and later were one piece
  • Real early front bumper is one year only design- though a 69 will interchange with it
  • Angle on end of front bumper reinforcement extensions was different
  • Hole spacing on front bumper outer brackets are different from 69 (holes on 68 frame are spaced differently)
  • PO-1 Wheel covers were 68 only
  • Door sill plates may have been unique – rumor is they were wider on early 68’s on the innermost side
  • Side rear view mirror placed a lot further forward on early 68s than later 68’s
  • True quad red tail lights
  • Side “gills” were plain body colur with no moundings
  • No stainless “tips” on the rear tip of the optional hard top
  • No bumper stops on rear convertible deck lid
  • Reverse light switch is unique to ’68
  • The paint formula for Lemans Blue in ’68 is different than it is for ’69 (the 69 blend was shared with the 68 Camaro which was different form the 68 Corvette) according to anecdotal evidence from “a DuPont guy”
  • Early ’68’s lacked the kick-up reinforcements behind the rear wheels that were added later in the production run.
  • No holes in the lower front valance on early cars – Dealers were instructed to retro cut these for improved airflow to the radiator.
  • 3 different sized headlight doors across the production run
  • 3 different metal surround panels/bezels to go with the headlights
  • 2 different wiper door grills – one with cutouts for washer nozzles, one without
  • Washer nozzles 2 different types depending on the wiper door
  • Didn’t have a wiper door close safety valve as found in 69 and later cars
  • Radiator core support has holes in it to allow the wiring harness to pass through.  This means they also have flat inner fender walls next to the support whereas later models have a notch to allow the harness to pass
  • Small block valve covers (L-79) were unique (Chrome stamped?)
  • Rocker covers were a two piece design that carried over into 69
  • 327 engine was unique to 68 C3s (one year only large journal)
  • Wiper motor is unique (wiring and opertation)
  • Wiper arms
  • 20 gal gas tank
  • Steering damper on the drag link was a part year option, later canceled
  • Body mounts were solid aluminum, later years were rubber (some early 69’s may have had the solid mounts)
  • Dash wiring harness
  • Front spindles are the same as 67`s and earlier. 69`s and after are different bearings.
  • Inner fender splash sheild were changed from stapled to push pin.
  • No hood insulation
  • Spare is also mounted on a ralley wheel. Was this also done on a 69?
  • Front bolt-on cross member doesn’t have holes in it, whereas later years do to allow for the radiator support to bolt to them.
  • External voltage regulator
  • Headlight / wiper door vacuum relays unique
  • Can wiper door actuator and connecter –  ’68 Wiper cans had 1/4″ shafts. Early ’69 wiper cans had 5/16″ shafts. Sizes (rod diameter) are dif between early 68/late 68, and 69
  • Headlight vacuum canisters
  • Hood latches located differently to later years
  • Smog pump on small block had relief valve
  • Frame on early 68’s differed from late 68s – bolt holes on frame horns and their extensions were of a different configuration.
  • Oil fill cap  – possibly same as on a 67
  • Intake manifold (has oil fill tube)
  • Door alignment shims
  • The 68 had a nose support bracket that was part year only, none for early models
  • Rear brake lines (top inlet on caliper)
  • Left side exhaust manifold (alternator mount)
  • Rear plenum vent tubes
  • Upper door hinge is possibly one year only part but is interchangeable with 69 and up. The difference is a shorter spring and the tongue configuration is shorter than 69 and up. (however some grinding may be required to prevent it taking a chunk out of door when fully opened as the door on my 68 can attest to.)
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14 responses to “The unique 68 vette – or why won’t that later c3 part fit

  • jim sieck

    Steering wheel hub on non tele is unique to 68

  • PJ

    Gas filler lid should be of riveted design rather not with screws.

  • Peter

    great piece… thank you for sharing. I am finding that the rear exhaust panel on a ’68 is also different than ’69 on. Maybe verify my observation and add to your list?

  • Paul

    the ’68 heater, heater box controls used all cables for controls where as ’69 & up had vacuum operated air & plenum doors. ’68 heater control was one year only. The stock exhaust manifolds had a one year design where the alternator base bolted to it on the left manifold. The front wheel bearings were the small ’67 style vs the larger ’69 style. I also think ’68 had the ’67 style/size front spindle?

  • Cee

    Ever locate a center wiper switch bezel? I need one too!

  • Steve Kalisch

    Valve covers, no filler cap but have PVC vent holes. Front timing cover and harmonic balancer, timing marks are the different.Cylinder heads, have no accessory bolt holes but have the temp sender, 67 did not have the casting raised to even add the temp sender. I need the bezel for the AC also.

    • Cee Smallwood

      I finally got around to retrofitting a 73 or 74 center AC panel into my 68. Like most others, the original single vent AC and wiper switch bezel had broken and there is no chance of welding it back together. Several yrs ago I purchased the used 70’s style panel but noticed it would take some modification if the center duct work to make it fit. It did require some cutting and removal of the duct plastic but at least now the bezel is installed and I don’t have the open gash in the dash with the duct staring at me.
      Doing some research, it would appear that the 69 up center duct would fit in the 68 and would have made the process easier. eBay does have some 70’s ducts out there. I may try this later since it would be a better fit than my retrofit job.
      You can buy new chrome center deflectors and foam seals to put in the bezel so all looks good.

  • Rick

    I just purchased a 68 conv and have been finding out about some of the things you have listed. This is a great list and I’m sure I will be referring back to it… Thanks for a great post.

  • Rick R.

    I have an early 68 with a mid November 67 build date. The wiper switch letters are blue. I believe later 68 production the letters were white.

    • azza2u

      My early Nov 67 build has the white lettering in the wiper switch knob, but with a good proportion of my car not being original hard to tell if it’s original or not.

  • Patrick Sullivan

    My 68 hood support differs from the 69 in that it does not have a bracket that bolts to the drivers fender. Aside from that the catch is internal in design and slides rather than unlatching when the hood is lifted to release it. I don’t know for certain, but it sure looks like a one year only item. Great list and I’m finding a lot of them on my January build convertible.

  • Wayne

    Engine mounts are listed in parts books as the tall and narrow style but the only ones that fit are the short and wide ones.

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