Thanks for the response..I will look closer at the brown wire in the wiring schematic. I would like to get the wiring completed while the dash is still out. If needed, I can just wait until I get the dash/batt installed and check voltage as you suggested.You only need a switched power wire when key is run position which connects to the violet wire, on 78 Camaro it is the heater switch power wire brown in colour which comes from the fuse block. Take a test light and see which wire has power when key it run position, probably the brown wire on connector, connect violet wire to that wire