Concealed by the bumper, there's a hole through the rear valance. I drilled a hole out of the middle of the trunk into the channel behind it about 8 inches to one side (no easy direct route into or out of the trunk area for critters/water/salt.etc.). Inserted a piece of PVC tubing (~5/8" od) through there and routed the wires through it. The capped connector usually hung from one of the safety chain loops, but I'm going to conceal it more on Da Red Dog. There *is* a lotta empty space inside that bumper, after all!
More advice for anyone doing this: do your wiring on the *left* side of the hitch because that exhaust coming out just to the right of your hitch will probably *melt it* if you hang it nearby. Also be very careful unhooking the (HOT!) right side safety chain immediately after a drive. Want to know how I know? =8^O