[lindstromjd]

I completely re-wired one of my trucks a while back with an aftermarket harness, and I am NO electrician. Seems like a daunting task, but easiest way for me was to figure out which wires would be grouped together, and keep them close (like with masking tape labeled "headlights, tail lights, under-dash" etc).

Just do one wire at a time. No matter how tempting it is to do multiples; it will confuse the hell out of you eventually. And don't cut anything at all until you're positive all your lengths are good (run the entire wiring harness, THEN cut). I ended up re-positioning some of my wires when I was done because I didn't like the way they ended up getting routed.