1966 dart problems, help

If that green wire that was never hooked up goes to the alternator then yes it could overchage.

Not correct. Without the green (field) wire hooked up, the alternator will not charge at all.

1966DartDude, go get the three books described in this thread as quickly as you can, to get up to speed on how your car was put together, how its components are supposed to work, and how to repair them when they don't.

For charging system test info and regulator options, see here.