On an old Phord once, I removed harness as one-pc or as good as I could and cut the covering around the wires open, but left it around wires. I then used the wiring diagram and the wires themselves, pulled one out at a time and made a new wire of color I picked and size and made it same length. Sometimes had to leave a little extra if old one was broken or changing location of part it goes to. I used the crimp on connectors you can buy anywhere or you can buy the same that need soldering if you'ld rather. I have stripped the plastic off crimp ones, slight crimped and soldered too. Or use old car harness parts ( I save old harness's when junking) and use wires with connectors already on them in place of old harness wires. You get more color choices that way too. OR, you can use old junk harness wires and still new connectors for more colors.
By the time you get several rolls of wires, lots of connectors or assorts and good wire strippers and the corrugated tubing to put it all back into, (heck with wrapping with tape), you can have alot in it. A basic harness from somewhere may not be that far out of reach. And it may be easier as most are marked on each wire what they are for. AND, you don't have to run the fuse box and parts exactly as orig anyway. Can mount under seat, or in glove box or such. Ain't this FUN?
