I have a 1987 Ford F150 4x4 has 4.9l will a 1996 Ford F150 with a 4.9l with electronics will they interchange. Will you have to change wiring harness?

 

It depends on which computer you want to use. 1996 ecm's are obd-II, so you'd need all the associated wiring and sensors to keep it happy.

 

If you want the engine to keep running like it's in a '96 truck, you'd have to carry a LOT of wiring & other parts from the donor truck into yours. But if you just need a replacement long block, it can be swapped into all the '87 wiring & emissions.