I guess this kind of knowledge will come to me with experience...
I need to ask someone if they suppose an '84 Trans Am headlight assembly will fit into my [wrecked ] '86 Firebird.

I sort of found my answer in another thread, but not completely sure.
Thanks in advance.

 

it most certainly will, i had a wrecked 86 trans am, i went to a yard and got a headlight assembly and fit right up, if your still not sure call the dealer and ask them for a part number on both headlights, the broken one and the one you will replace it with.

 

Physically it will fit, but I have heard that the wiring changed around 84-85. Might not work properly without rewiring. Not sure.

 

Yeah, I've read something about 2 wire vs 3 wire configurations. Does someone have more info about this?

 

If you need just the mounting/hinge assembly I think they are all the same for all 82-92. The motor however is a different motor. I'm not too sure, but I believe 87 they changed to the 2-wire motor. If you look at the two motors, the newer motor has one dimple in the **** while the older ones have 2 dimples in the motor.

 

ya its the same if the wires are diffrent then just put the other bolb in.