Ok, I took a look, im no electrical genius, so bear with me.
For power they tapped into the bolt that connects the battery to the fuse block located at the front of the engine bay. There are 2 large red cables that connect the battery to it, these are secured with a small bolt and nut. They simply attached a wire to it with an inline fuse and then ran it around the engine compartment towards the back of the truck.
Now, this is where it get a little lost. The wire runs on the driver side and near the firewall there is another inline fuse. On one side of the wire a very small guage blue wire with orange stripe runs into a factory wiring harness. The harness is pretty substantial and taped up pretty well, I have no idea what it is for, the wire simply disappears into it. On the other end is a white wire that enters a piece of loom and goes with the wire from the power source to the back of the truck.
I hope its not too confusing, but, thats all I got!