ASSEMBLY. AND INSTALLATION VERSION 2 1. Three the Nipple with the Key Washer and Hex Nut to the Cross bar, then attach the Cross Bar to the Outlet Box by using poss Mounting Screws. 2, Make wire connections: Smooth wire (w/marking) from the light to black wire from power source --Ribbed wire (wio marking) from.the light fo white wire from power source --Attach the ground wire ta tha cross bar with a green ground screw. Carefully tuck wire back into the OUTLET BOX 3.