The grill and front end parts will work if you want to change everything over to have the new style headlights (the rounded ones) instead of the square ones (the Westys) which I think were only used for 1985. Some people like the square ones. I like the round ones. i believe you are speaking about the difference between AEROdynamic lights, and rectangle 200mm lights?The later cars have the "big bumpers" which attach differently to the fenders (2 points of attachment on either side). They can fit the older cars but are different.you can swap big bumpers onto a small bumper car, but idk whats required bracket/fabrication wise to make it work.. smalls dont even mount to the fenders..The interior electrical and doors (as mentioned) are different, as is the dash, I believe. The new doors would have the long windows without the small triangular fixed window at the front. The 2 door and 4 door parts aren't compatible anyway, except for parts like door handles and window cranks. the later cars had a knee bar, instead of the cubby pockets and stuff.. also, the fuse/relay panel is completely under the dash on the later cars, all integrated into one unit.. the wiring is completely different between the early and late mk2 cars..Seats are different because of the seat belts but can be made to work by swapping some parts.the 90 should have dual seatbelts.. a separate lap belt and shoulder belt, and the shoulder belt attaches to the door..I think the hatch will fit, it is the same shape but it's different. The later cars had the hi-mount 3rd brake light and the window wiper motor is wired differently, with different color wires and such. I have a newer hatch in my 85 and it all works (including the third brake light) but I had to do some electrical wiring and refer to a wiring diagram to get it right. good call about the hatch, i forgot about the extra brake light they added in 86..It all depends on how much extra work you want to do and how much you want to retain the characteristics of a 1985 car, which was a "one-off" car year for VW, this year was the first mk2 and yet it they changed a lot of things by 1986, so many pieces are 1985 only.
i believe you are speaking about the difference between AEROdynamic lights, and rectangle 200mm lights?
you can swap big bumpers onto a small bumper car, but idk whats required bracket/fabrication wise to make it work.. smalls dont even mount to the fenders..
I would stick with the small bumpers. I have a '91 and the big bumpers are a PITA, if you want to get under the car, as you no doubt will want to do
Big bumpers might help with fuel mileage.