New e-body harness

I'm working on getting my Challenger back to daily driver status but I've been fighting little electrical gremlins. The wiring is all original except for what was hacked into during the years before I bought it in the late 90's. I'm thinking it might be simpler to invest in new wiring and do the whole car right rather than hack further in an attempt to fix previous hackery.

Where is the best place - or is it even possible - to acquire a new wiring harness for a 73 Challenger? Again for the whole car, not just the engine bay.
Author: Manimal