Abstract: Lighting unit assembly which is adapted to be mounted in a panel comprises a housing having wall portions which define a plurality of enclosures, each enclosure surrounding a lamp bulb mounting site. The lamp bulbs are mounted in removable lamp bulb connectors which have contact terminals which are in contact with the bulb and are also in disengageable contact with terminals in a tap connector. The tap connectors are mounted in the housing adjacent to the lamp bulb sites and the conductors extend through these tap connector housings and are electrically connected to the tap connector terminals. The lighting unit assembly is completely pre-wired and assembled so that when it is inserted into a panel, a harness connector on the conductors in the assembly can be immediately coupled to a complementary harness connector.