this is from my install
the way i did it, is i mounted my lights on the braces for the back bumper at the ends of the hitch. its a U shaped brace su u may wanna modify a couple washers to fit, ot itll loosen up on ya.
as far as wiring, i used 25ft or so of 14awg outdoor extension cord, 3 wire. ran from the battery up to my driverside tail light. then, ran extension cord to each light and convened everything to the tail light. using 1 30amp relay... u gotta find the wire on your trucks harnes to see which one is hot when in reverse, thats ur back up light, that u gotta splice into and run a short wire from that to the 'switch' pole on your relay. then each light gets a pole on the relay, and you gotta ground it. i used a bolt for the tailgate latch to ground mine.
Now, i was going to tap into the harness ford was nice enuff to provide, HOWEVER. that harnes is too weak to handle a 55watt bulbs. so u need to run ur own wiring.
the extension cord worked good, cause i used 1 wire of the cord for the backup lights, then anoother wire for my tail gate switch, personally, i say get the extension cord.