I would say the easiest thing to do is keep the V belts, but I wouldn't.
I'd go with the serpentine setup as its more efficient, more durable, easier to work on, and quieter. That's why all the OEMs switched to them years ago. That is a no brainier in my opinion. It also lets you install the much more powerful 130A 3G alternator as nearly a bolt on item if you buy a later model Fox setup. Oh, and although this is lofty and you may never get there, it also paves the way for practically every super charger kit.
The most straight forward way to swap do would be to buy an entire (junk) donor motor for all of the brackets and buy a setup that suits your needs (I'd find a way to make the Fox setup work). At my local junkyards the crap engine pile motors are about $50-$100/ea depending on what they are. Obviously I would buy a new water pump. Just make sure you get the proper rotation direction and length for the accessory drive you purchase. Just about any parts house should be able to get you setup as long as you know what vehicle the motor came out of. You may also have a mechanical fan issue depending on how far the fan is from the radiator. Again, simple answer is an E-Fan (good thing you've got that 130A alternator now).
'91 GT 5 Speed
Last edited by Maxwelhse; 06-26-2014 at 05:55 PM.