67 318 magnum swap

For me it wasn't so much about replacing the wiring to the current components ( I left most of that stock anyway except for installing relays for the headlight circuit ) , it was about not having to wire in all of the new stuff from scratch. Heck, either way is a bit of a chore, but with the donor harness it's already bundled with all of the correct connectors and such. In my car the only things that are powered from the old harness are the relays in the PDC, rear lights, gauges and A/C compressor. Everything else draws main power thru the PDC, including the cooling fan, amp and stereo.