If you pull the roof rack covers, you can bore a half inch hole through the roof and into the cab of the truck. A little spray paint to prevent rust, and then if you use an extra large (4 foot) zip tie as a snake, you can fish the wires through the hole to the back of the car without even taking down the headliner (the D piller trim needs to come off though). From there I connected to tie wires I had run earlier when I had the interior of the truck apart.
Here you can see how the wires come up through the foot

Holes drilled through the bottom of the foot into the roof

How the connector will mount

The Final Product


