If the current alternator is external regulator, Tuff Stuff has a 100 amp version that is pretty good. I installed one on my 57 when my stock 63 chevy alternator could not keep up any longer. the rub, you cannot use a mechanical regulator, you have to use a heavy duty electronic regulator, which Tuff Stuff also sells. Mine has been installed for a couple of years now, not a single issue.
