After about 156,000 miles, I think my alternator is succumbing. I note that these are available in the original 115 amp and upgraded 200 amp versions. This is a stock '92 coupe. Is there any reason to opt for the heavier duty unit? Any recommendations? You can buy these things from practically nothing to maybe $325 for a Bosch rebuild. I'm thinking a rebuild is OK, but they are available for a lot less than that number, in the $200 range.