Heavy Duty Alternator - Can I overcharge the system?

[Bubsco]

I have a 69, 350 with dual batteries. Came that way when I bought it. I am upgrading the system and adding an isolator, inverter to run goodies, and new battery cables. One standard battery and one deep cycle for the goodies. I think I need to add a heavy duty alternator as well.

My question is do I have to worry about over doing it. I assume (and you know what happens when you assume!) that the internal regulator in the alternator will make sure of proper output. Do I have to worry about old wiring? Can I overcharge the system? If I upgrade, what size (80, 105, 140 amp) etc? Any manufacturer preferences?

Thanks as always for all the expertise in the forum.