Need help/advice for converting Volvo TAMD70E from V-belt to Serpentine and adding an alternator

[sndog]

I have twin Volvo TAMD70E engines. I was wondering about upgrading the alternator to a 48V, 200amp. I have researched and found that requires me to change from a V-belt to a serpentine belt. I was thinking of also keeping my current alternator (12V@80amp), but may avoid doing that for simplicity sakes and just use a charger to keep the 12v starter battery charged.

Thank you as always in advance.