Overcharging Problem

Hey guys so i just swapped a 360 into my 66 cuda it had a slant 6 in it before. I have ecently gotten a new alternaor and i have gone through 3 voltage regulators. What is happening is that as i am driving my ammeter goes all the way to charge and the wire going to that gauge gets really hot and starts to smoke. What could be causing this issue?

Im stumped

Thanks