I took the covering off the dash wiring harness today because I need to shrink it down to fit in the 39 cab. I need to put 10 lbs of stuff into a 5 lbs size bag (or shrink down a 60" x 24" deep laid out wire harness to a 46" x 14" area). It appears the black box must be a body control module because there is at least 1 wire from each circuit (cruise, wipers, heat & turn) going to it. Guess I'm going to find out how things will function without it, I will try to unplug it to see what works and what wont. I'm at the point I might just wire the project myself from scratch. Gene