1973 Dodge D-200 Time to hang a new harness

I was gonna ask the OP what wire(s) are causing you grief? 1 or 2, or many of them?

Since you are near to the coast there in WA, are the wires corroded green inside of the insulation when you strip the wires back or look at connections? If so, then moisture has penetrated deep and you are better off with a new harness, IMHO. If that is not the case, and most of the crimp areas and the copper wire look clean, then making repairs to the few 'problem children' wires is better.
Well, we caught the alternator wire before it fried, then ran it through the firewall so it would circumvent the vulnerable fuse panel.... after a recent bout of no blower, no wipers... they got them working and 10 minutes later, many other wires melted on the back of one of the front panels, (not in the glove box).... hence the expensive re-wire due to start on Monday