Car is overcharging. Please help!!

My buddy Brock has the same exact problem. We tried two alternators and they both do the same thing. One has one field wire and one has two field wires....they both tested good.

He has blown up/melted two regulators.

He had no problems before he painted his engine bay.

I have not been able to get back to him to help him but I was going to look at grounds at the firewall and from the block to the firewall.

Would running a ground from the battery to the regulator help? That was my next option if we couldn't get a good ground on the firewall.

I'm in the same over charging boat.....need help.

Mop