Tail light wiring

[OgCoda]

So i just got my engine dropped into my truck and got it all running. everything is working good so far but the taillights/brake lights and blinkers wouldn't work... So i got up under the rear of the truck to find that someone compltely ripped the wiring out of the truck... The wiring that is somewhat left is all rotted and gnarly. So what i'm getting at is, Does anyone know of a rear section wiring harness i could get for my 71 longbed c20? headlights work fine just everything from the rear of the cab is ****ty.