I have a 2013 F350 that I added the factory 7 way plug in the bed. It's part # BC3Z 13A576 A : Wiring Assembly - cost $68. It's the same plug used by Ford in the bed when you order the Hitch in the bed option. It comes with a plug (I believe it's a small 6 plug unit) at the end of the wire that plugs into the wiring harness under the truck near the spare tire if I remember correctly. No splicing into your wiring harness. It's a plug and play deal. All Super Duty's come with the same wiring harness, so adding the 7 way plug in bed is super easy. Hardest thing is cutting the hole in the inside bed wall!