I posted this on the electrical forum with no response, so maybe with more traffic here someone can help. Do the relays and voltage regulator need to have bare metal contact when they are mounted to the firewall, or does it matter? Just painted the firewall, and there was a ground strap that fit under one of the voltage regulator mounting screws. This brings up the question of how many ground straps are there on a '72 Cutlass, and where is there proper location? Thanks, Chumley

 

The metal can be painted. Afterall, the factory painted the chassis first and then installed the drivetrain. However, the metal screw that goes into the firewall should have a serated washer on it. That helps make the contact between the wire-end connector and the underside of the screw head.

I dont specifically know the answer to the second question, but generally speaking you need a ground strap from: engine to body (firewall), body to frame, battery to engine or frame.