No Back up lights anymore

[LarryG]

I didn't want to splice into the truck wiring for my new back up lights so I made up a pigtail to go from the truck trailer wiring plug to a new plug mouted on a bracket off to the side (supplied with the White Knight lites), with a split off with the three conductors to go to the new back up lights. Nice idea, I thought. Well the female plug I bought from UHaul I think is a little short on quality, and I think when I reassembled it after terminating the wires, I got it in the shell rotated exactly 180 deg. I did get the new lights to work in the "always on" position, but it never did work with the truck's back up lights. I did blow the 15 amp inline fuse that came installed in the hot wire at one point (I've installed and reinstalled this thing several times) and replaced it. Now the truck back up lights don't work at all. I checked the fuse for the back up lights in the fuse panel on the left side of the dash - even exchanged it with the spare to be sure - and I checked the power distribution box under the hood - everything seems to be ok there. I'm going thru the wiring diagrams in Haynes with out much luck. Does anybody have have any advise as to what else might be wrong? Any circuit breakers that need to be reset? Fuseable links? Right now I don't have any power to the center post in the trailer plug with the truck in reverse with the engine running - not something I like to check by myself even with the parking brake set and the wheels chocked.