First thing I did before tackling any re-wiring was to run a 12v direct to batter power source to the cab. I got myself some stereo amplifier and soldered on some lugs. One side is connected to the starter positive with a 200amp circuit breaker (cuz thats all I had on hand) and then it goes through the tunnel to this little distribution block right by the fuse panel.
So now that I have a direct power source in the cab, I need to relay my lights. I got this harness and relays off of ebay. Its from china, but its pretty decent. I wired it in, made a little bushing through the wall and got to my distribution block. Now I have switched halogen lights direct to battery.