Lighting problem

Im new to the site and the '72 Duster I bought. Only lights that work are headlights (hi and low beams), both blinkers (also the cluster blinkers work), the oil dummy light, and the highbeam light in the dash. The rest of my cluster lights dont work (put new bulbs and sockets in), all the running lights dont works, and no brake lights. Im missing one reverse bulb, but I wouldn't think that would cause it. Any one got any ideas? I dont know where to start, i'm not much of an electrical wizard. Thanks.

The car is completely original right now except the interior I almost have complete. Its a Gold Duster with a/c, /6, auto, and is a one owner from AZ with 64k miles.