Engine wiring harness. 96 4.0 4x4

My jeep is throwing codes for injector circuit malfunctions and high voltage from the O2 sensor. The O2 and injector wires run together over the top of the engine in a plastic holder. I removed the wires from the holder, loom, and electrical tape as best I could. The tape was melted to them on the bottom and the wires were stuck together. I want to just replace the engine wiring harness, but the dealership can't get them anymore and if they could it would be about $900.
Does anybody know where I could find one besides a salvage yard?
I would rather not risk replacing the wiring harness with one with a different problem.


Dustin

Still looking for suggestions, but if I do go to a salvage yard I think I would prefer to pull it myself for the experience before working on my own and to keep the cost a bit lower. Can everything be unhooked from above the engine besides the upstream O2 sensor and wiring that goes through the firewall? How many places does wiring go through the firewall? I see 2 spots, both on the drivers side, one of them might go to the wiper motor.

Dustin