cant get the darn lights to work

Since I got the new taco.. I took off the stuff from my old taco to install on new. One is the PIAA backup light set.. it works well.. until I start installing on new 2014 taco.. the damn thing wont light up when it shift to reverse. It got the relay and fuse set and switch for manual bypass. ( taped the manual switch which I don't use, had set on auto) .
I am sure there is a bad wire that was broken in the process of restalling. So here is my idea to remove wires that comes with the kit, install new wires and relay fuse direct from battery to the light source. and one wire to tag on the reverse wire at tail light.
If this correct..let me know... thanks

 

That's what I would do. Don't forget the other ground (wire should run from reverse light to relay, to ground to complete circuit).