In the Factory Service Manual. You can buy one on-line or some larger Library systems have Factory Service Manuals to check out.
Autozone's website has free electric wiring diagrams
go to auto parts store and buy a haynes repair manual and it has all wiring diagrams in it along with just about everything to do with your jeep
The Haynes Jeep Cherokee 1984 - 1996 book has 7 different diagrams which show how to do that repair.
Chiltons Auto Manual for Jeep Cherokees has diagrams for each of the jeep fuse boxes
go to wiring-diagram.com. for @ $13 you can get the wiring diagrams.
there really is no difference in the engine it will be the computer and electrical connections
Autozone.com has free wiring diagrams for your vehicle in the "Repair" section.
Looking for the radiator cooling fan air conditioning wiring diagrams for 2000 cherokee laredo
How do I change a headlight bulb on a 1998 jeep grand cherokee?
www.autozone.com Provides 1 electrical (Main) and 2 body wiring diagrams. http://www.autozone.com/servlet/UiBroker?ForwardPage=/az/cds/en_us/0900823d/80/1f/ec/6b/0900823d801fec6b.jsp This will provide all wiring diagrams for Wrangler from 87 - 95 bruce
A 1991 Jeep Cherokee computer is what fits a 1991 Jeep Cherokee.
I got one from my Jeep dealer today - just walked in and pretended to want to buy a drain tube and the dude did not know about what part it was so he went off and printed out 3 pages of explosion diagrams. I am in Australia.