Heavy Duty Alternator

I was just looking at Advance Auto's site and I was hoping they had both in stock at the store here....they have neither. I think, when the time comes, I will see if i can't get one of each and see how the mounting works out. Either one would be a nice upgrade. I really like the design of the aluminum case with internal fan(s). It looks similar to the original and it does not look like a typical GM alternator, plus it's small.