Just finished a 4.0/AW4/NP242 swap on my 1984 Wagon. I didn't get the chance to really document the build here on the den due to time constraints, but I'm hoping I can share a few of the things that might help someone else in the future. I'll post stuff I can think of that took a lot of problem solving, but let's do this in an Ask-Me-Anything format. Post something you’re curious about on the build, and I'll try to answer and give details.
The basics of the swap:
4.0 out of a 1999 cherokee with a rebuilt 1995 7120 head
1995 AW4
NP242 out of a 1998 WJ with a SYE
Full 1995 XJ wiring harness integrated into Eagle harness
YJ air filter housing, XJ coolant reservoir, and XJ evap canister all in engine bay
floor shifters and trim from 1990 XJ
In-tank fuel pump
Included a pic of the finished engine bay.