I'm gunna do the 4.0 swap.
going to pick up: $350 for 93 yj 4.0 complete with, harness, flywheel.
I'd spend that much on parts to rebuild the 4.2.
Plus I'll have a fresh rebuilt carb, nuttered dist/ign module, and used 4.2 to sell.
Plus, with the upgrade from 87 to 93 I get a better alternator, Ignition, and elect speedo