Restoration of a Wiring Harness

I just went throught the same thing last week. I used a little solvent and a tooth brush to clean up the connectors and some solvent to wipe down the harness and wires. I removed loose tape and replaced it with a hi-temp electrical tape. On tape that was solid, I taped over the top again, after first cleaning it well. I checked all the connectors for loose connections (found several) and had to take some apart and recrimp. A couple of old splices were cleaned up, soldered and shrink wrapped. Not brand new, and potentially with a few problems, yet (although I headed off a few that were inevitable), but 300% cleaner for $10 worth of tape and 3-4 hours of time.

Good luck