im not 100% positive how the hook up, but my best guess would be there is 2 wires. positive and negitive, and you splice it into the tail light.
bascially just take the neg and ground it to the truck. and run the positive into the taillight positive. you can get a little i think they call them T clamps. you put it over a wire and close it. and it cuts into the wire with out cutting the wire in 2. then you can put a connector on the LED bar and it plugs into the clamp. very easy, take about 10 min.