you might search www.forabodiesonly.com & www.bigblockdart.com & find an original harness for sale. That's what I did on my 65 dart & I cleaned the terminals/ends & installed it & that took care of all my issues. iirc I bought mine from a gentleman named Steve Remington. Price was very reasonable. On another I took the harness out & laid it on the floor & made a new harness right next to it by soldering in 1 wire then cutting/tossing that identical wire on the nearby harness till the old one dissappeared & then new one took shape. On that one the wires in the harness were all there but some were brittle/terminals corroded so I bought spools of wire of the correct colors & gauges & went 1 gauge smaller on most of the circuits. I cleaned the bulkheads/bakelite connectors etc & NAPA has packard 56 type brass 1/4" terminals 725145/725147 male/female