No power lights etc but ignition turns over?

"There are three hot wires." This is misleading. The yellow is not a feed. It is a ground switching leg. It is hot at the cold end of the dome lights it is not truly a "hot wire"

Ironracer you need to stop posting to these old threads, and start one yourself next time.

The tan is an OUTPUT from the dash dimmer rheostat. IF YOU have park/ tail/ marker lights and nothing on the tan WHILE THE KNOB is twisted to the left, then you have problems in the switch, most likely a bad dimmer rheostat