Long story short, completely replacing all the wiring in the rear end for a new harness. When my dad bought the truck, it never had a trailer plug on it, so I had to wire it in. Almost 20 years later, I cut everything off and am wiring in one of those nice USCAR plugs, but now I'm left with two wires on the truck and three on the new harness. The light blue and light green coming off the truck are what's troubling me, I already have the proper green hooked up. I have lights hooked up and working fine, but I want as few as possible wires dangling around as possible. The truck does not have a purple wire for backup lights, so I won't be using that, but I need to know what to do with the other blue and green wires and if they go to the other blue and black wire. Or shoot me a link showing me a color code because everything I find says the truck should have red, black and purple wire left over, which it does not. The truck is a 2001 Silverado, standard cab, 4.8, 2wd, auto.

 

Ok, so I FINALLY found what the other wires are coming off the truck, the Light Blue is for a 3rd/high mount tail light and the Light Green is actually for the reverse lights. Hope this helps anyone else looking to do some wiring like this.