Alternator question

It "will work" up to a point and after a fashion

The voltage drop (search some of my posts) that is LIKELY in your aged? original? wiring is likely to cause trouble

And.......if this unit is a larger output by substantial amount, you may have wiring issues "in a little while."

Start by reading this article as to the "why."

http://www.madelectrical.com/electricaltech/amp-gauges.shtml

Even "Ma" knew this was a problem, because the larger 60+ amp alternators got upgraded wiring in what was known as "fleet wiring."