Should not be any major differences. Main one is the intake is cleaner on the '94. Other main difference will be in sensors and emissions/EFI stuff. If you move all the '85 components onto the '94 engine, it should be pretty much compatible. 2WD tranny will not have the right tailhousing to bolt up a t-case. Not sure of those can be swapped or not. But the '85 tranny/t-case should bolt right up to the '984 engine.