I'd not really thought about having a 7-pin connector mounted inside my truck bed until the salesman asked if I had one there. I didn't, so I thought I'd do it.
I looked underneath at the wiring running to the factory connector, and was a little scared to cut and splice. I've never had good luck doing that. So I just made a jumper that would use a vehicle 7 pole connector, approx. 3 feet of properly sized wiring and a 7 pole trailer connector.
I bought the 7 pole vehicle connector and the 7 pole trailer connector at a local auto parts store, found a spot between the wheel well and tail gate, removed the small panel underneath the bed to verify there was enough room between the bed wall and the truck body, used a two inch metal hole saw and drilled thru the side wall of the bed where the connector will be mounted. I already had the correct wire sizes that were needed. I connected the wiring to the vehicle connector and fished the wiring thru the hole and routed along the bed frame to the rear factory connector. Connected the loose ends to the correct terminals on the 7 pole trailer connector. I then tie wrapped the cables neatly underneath and left enough slack to unplug if needed to use the factory connector. I used a small bungy cord (about 6") to mount to the trailer connector and frame of truck to hold the trailer connector up and out of the way when not needed!!!!!
Once completed, checked for correct voltages. All Good.