I was hoping we could have a thread that pointed out little differences here and there for different parts around our cars. i have noticed there is a lot greater parts diversity in Mk3s than the Mk2s I'm used to.
Borne from these (some helpful info for Mk3 too):
here are some examples I've found:
side molding- all texture molding is held with clips, and most painted molding is held with tape. Except the 1994 Jetta GLX, which has painted, clipped 4 door molding, and Mk3.5 Cabrios, which have painted, clipped 2 door molding.
dashes- it seems pretty common knowledge, but to have a fully thought out thread, I'll include it. Early Jettas came with "Vento" dashes with light up vent on/off flaps (beaver and black). Then there's the "normal" mk3 dash (also available in beaver and black), and the dimple dash from Mk3.5 Cabrios (black only). Upper and lower glove boxes can be installed with slight mods into any car, though no dimple dash ever had an upper glove box. Cabrio 3.5 has plastic dash grilles with a frame, the rest seem to be metal?
speakers- early Jettas had the speakers in the rear doors, like Golfs, and later Jettas moved them up to the shelf. But all Jettas have the holes in the shelf, so you could, theoretically, swap in the rear door cards or shelf, to get an extra pair of speakers in a car that doesn't have them. Also, you can swap the handle molding from the rear doors to the front (you'll lose mirror controls) to get extra tweeters in the front doors, making for a total possible 14 speaker locations in a Jetta, 10 in a Golf.
o**** handles- There is a smooth style, and a style with a lower "trim" near the mounts. Same with the Black Passat handles that swap right in. The B3, and B4 will both fit like factory, but they are slightly different look wise, in the same way the Mk3 are.
Passat B3 domelights are black, and will fit in a non sunroof Mk3 with a pigtail swap.
The late SLC Corrado sunroof switch, is the same style as the early 94 Mk3 sunroof switch, just in black, and sells for ALOT secondhand. Upwards of $200 sometimes.
switches- Cabrio 3.5s have red lighted switches (obviously), but they also have the center mounted hazard switch. it seems all you need to swap to that switch style is the switch, and dash and column harness. You'll also need the 3.5 column clamshell, but it might be different for immobilizer cars? All early cars got 3 position switches. 93-early 94, and the GLX and Golf Sport/LE, and Cabrio of those years also came with a 3 position with Fog switch. They also got Bubble style AC and Defrost switches, and all the other switches are a different construction then the 95+ switches, that are PCB board based, instead of just resistor based.
misc interior- black Cabrio sunvisors fit right into other Mk3s, a Passat B4 above-mirror block-off can clip into a Mk3 header panel, Cabrio 3.5 chrome door handles, ebrake button, and shift knob are all Mk4 style, Cabrio 3.5 locks are laser cut (like Mk4), not sure if there's an alarm module that will work though? Corrado sunroof control/dome light in black fits Mk3. Mk3.5 3 spoke wheels fit in any Mk3, and the airbag is exactly the same as the same style Mk4 wheel. The Mk4 wheel fits as well, with literally 5mins of modification. The 3.5 wheel is WAY WAY overpriced.
engine- Mk4 12v and 8v parts are pretty much all bolt on, any specific upgrades besides intakes? Mk2 metal flanges can be an upgrade if you get the sensors to work too. For A PS delete on ABA< run a VR6 waterpump pulley. The clip caps found on Mk3 injectors, and coils (2 and 3 pin respectively), can fit on almost anything in the engine bay, and hides the little bit of colored wire for a clean look. Mk4 throttle plug caps can be scavenged for the OBD2 Mk3 throttle plug. AEG exhaust manifold is tubular and bolts onto ABA's, The Mk4 12v manifold requires very little modification to be fitted, and just a RPM window switch to have the shift rod active.
brakes- all brakes are swappable pretty much. 9.4 on Canadian 1.8, 10.1 on ABA, 11 on early VR6 and 11.3 on late VR6. Rear disc aluminum calipers can come from Mk4 or late B5/B5.5 Passat, A4's ect ect., and Cabrio 3.5s have the hoses stock.