I got a 51 Dodge Coronet which I've been having a problem with. When I take it out for a run. It's fine until I shut it off. It will take 20 minutes to cool down before I can start it up to take off. I figured it was either the points, could, voltage regulator. I tried to change the points and didn't succeed. I changed the voltage regulator. It turns over but doesn't start up. Now I can't even get it to turn over and no electric out put. I tested the battery and I get 6v. The head lights won't even turn on. Any suggestions