I have a love/hate relationship with wiring. It's a daunting task that requires a lot of fore-thought and methodical work, most of which is hidden. The result is that nothing happens, everything works, and there's never any problems. So you do a lot of work with very little to show for it. I've re-wired several cars (old and new) and I think adding race gear with additional sensors makes you a glutton for punishment
I'd like to see the results of your new/old re-wrapped harness and the heat shrink tubing/expandable covering is a cool touch.