The Reenmachine custom lighting system is a plug-and-play setup that can be installed in about an hour. This version fits '69 Mustangs or any car that uses four 531/44-inch lights. The included wiring harness is plugged into the car's existing headlight harness via one of the old low-beam headlight plugs. From there, the harness is routed and connected to power and ground, then the headlights are installed. Some legs of the harness are extra long to accommodate various mounting locations and routing. If there's excessive leftover harness length, slack can be cut out and the wires can be respliced together. It can also be coiled up, tie-wrapped together, and tucked out of sight. There's plenty of room in the cavity behind the headlight buckets to hide the wiring. Reenmachine also preinstalls the H4 halogen bulbs in the Delta headlight housings prior to shipping the systems.