Yanmar 3hmf alternator upgrade

[CapnBrown]

I have an 80's era 3hmf whose alternator stopped working. It has a lot of corrosion and I'd like to just replace it now that I'm drying out my engine compartment and want regular dependability. The replacement part is a 35amp Alternator of which a number of aftermarket companies readily sell. I would like to have something that will charge at a higher rate as I don't run the engine for very long. I try to keep the engine running for 20 minutes minimum but that is already longer than necessary to get sailing.

Anyway, I heard the 80 amp alternator requires so much tension on the belt for the 3hmf that it will damage the water pump unless a second belt is added. I'd rather not go through so much trouble and think maybe the 55 amp alternator the 3GM's come with would be a good balance to keep a single belt with a little more amperage. Does anyone know if putting the 55amp alternator designed to fit the 3GM models will mount up without a problem and if this is a reasonable thing to do?

Or am I asking for trouble and just go with the 35amp stock alternator?

TIA