im pondering swapping a fi 5.0 into my 80. i plan on buying a whole donor car so i get all the parts. how bad is the wiring part of the swap im used to carbed motors not fi.
-grab an entire 86gt efi harness, front to back, literally every wire. Swap it for your current harness, plug and play efi action
-contact windsor-fox.com, for less than $500, you can send them a mass air efi harness (just the engine harness part) and they'll convert it for plug and play action with exact directions to your existing wiring harness
-go to foureyedpride.com. There are a few guys there who have done this conversion splicing in an efi harness from an aero car with no other help, just knowing where to cut and splice. Those guys can give exact directions.
I almost did this swap to an 84 notch, but changed projects at the last minute.