Alternator becomes a super charger.

[74Rallye]

My '74 Rallye Charger has a problem with the charging system and I need some help! The problem is that alternator will intermittently charge at a level that makes the head lights burn bright white, the amp meter pegs to the charge side, and sometimes I smell the wires starting to melt. The headlights will become brighter with more RPM. Everything under the hood is new. I have ground buss wires on all of the firewall mounted modules. The negative side of the battery has a cable going to the frame as well as the motor. I tried to eliminate any possibility of gremlins when I rebuilt the car, but that didn't happen.
Surely someone has seen this problem before. I would guess that there's a ground connection somewhere that's intermittent. Maybe the battery is loosing it's ground connection and the voltage regulator is telling the alternator run wide open. I'm not sure, so I'm asking for some help on this one.

[Chryco Psycho]

Change the voltage reg

[Plumcrazy]

Also check the green wire between the alternator and voltage regulator to be sure it's not rubbed through and touching something that's grounding it.

[74Rallye]

Thanks for narrowing it down to a good starting point. I'll check the wires, then go for the regulator if everything looks good.

[Highway by the Sea]

Have the alternator tested at an auto parts store.  Mine melted a while back!