The main 5-wire harness is in the normal location along the frame for the marker and brake/tail lights. For the topper, the wiring enters near the license plate, then splits off for the license light, signals and third brake light. All the wiring inside the topper is housed in flexible harness covering from the local auto supply house and the lid wiring is routed over to the hinge area on the left side then up. All lights are LED and the signals are sequential arrows. The third brake light has a seperate modulator, flashing at a different rate than the one on the Wing's spoiler. Makes for an attention getter, for sure.