Car is overcharging. Please help!!

I had the same problem it was the voltage reg. on the firewall.It was not grounded because of paint made my alt. go bad. All of it went bad.I replace both of them one by one to find out the problem.When the reg. cant find a ground it shorted all of it,so i grounded the paint of the firewall were it bolts to and that was that. Something so small cause all that problem.I thought i put my two cent in anyway.