The vehicle : 1992 Isuzu Trooper - standard model.. i.e. manual crank windows, manual mirrors, no fog lights.

How do I tell if I have a 60 or 75 amp Alternator? I'm doing a bunch of work to one of my troopers. I yanked the Alt. out of it to clean it up before I put the truck back together. I just happened to have a brand new never used 75 amp alternator for my other trooper sitting in a box so I compared the two and they both look identical. However I was speculating that only the LS models with the power windows, fog lights, headlight wipers.etc. got the 75 amp Alternators and the rest of the non loaded Troopers got the 60 amp Alt. So yeah back to the original question, How do I tell the difference??

Thanks,

- Ryan