The head swap is realitively easy. There are many write ups on it...do a search in google. You have to plug one row of water jackets with epoxy and you need your head bolts drilled out to Half inch...or you can buy new stock ones and get some connicle washers I've seen a write up on this as well.Transfer the head Intake and exhaust from your cherokee and give a call to HESCO for the wiring harness for the MPI Conversion they make...unless you like splicing. Hesco also has the external fuel pump for fuel inejection and the piece you need to hook up your speedo to the ECU.

I have the Hesco MPI conversion on a 95 head and I think that their wiring harness only splices into the original wiring harness by 2 or 3 wires.

There is a ton of info on the net about the head conversion and a 4.0 swap either is a pretty slick deal.

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