I ran mine under the top edge of the tray above the "utilli track" rail up to the brake light, popped out the light and ran the wire into the tail light cavity, then spliced
into the brake light wires, but because the brake and tail are one globe you will find three wires where the light in the bar only has two, if you connect to the wrong
ones you will have it coming on as a tail light but no brake and when you put the brake on it will go out.
I connected the red and black stripped wire from the bar light to the green wire on the other wire from the bar to the black and white striped on the brake light.