The biggest problem I have ever had with D-W trucks is the bulkhead connector, it seems like sooner or later the main hot wire from the alternator fries.
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.
