I looked tried that route, but it was an automatic tranny and it was too long to fit in my wrangler. Good luck though.The old 4.2 has a nasty clunking, sounds like a diesel.
So after much searching got my self a 4.0 5 speed 96 cherokee.
The plan is to swap cherokee engine, tranny, all the wiring and have a 88 yj with an OBD2 port under the dash.
Wish me luck