A/C is like black magic. I lot of people I've met claimed they knew how to repair them but when I asked for help nobody knew how. Two years ago I got tired of having a bunch of vehicles with broken A/C (wife didn't enjoy it either). I decided to figure this top secret stuff out. After a lot of reading I dropped the cash for some good quality tools and tackled the my first A/C repair job. Since then I've repaired two more. It's time consuming, the parts aren't cheap, and since I'm not a repair shop with a leak detector I'm still doing some guessing but the rewards have been worth it thus far. It's not a quick easy job by no means, but it was nice when I had to turn the A/C up in the car yesterday on the ride home because it was getting to cold.
There is a serpentine clutch available for the York compressor, but I can't remember the details. I do know the York compressors came with at least two different cranks. The end of the crank where clutch attaches is different so the clutches are not interchangable. I'm thinking a serpentine clutch was used on the biggest York but it's been a good while since I researched it (my memory isn't very good). I do know there is aftermarket support in the form of a serpentine clutch for the biggest York, but it isn't cheap.
Onboard air rules. There are countless articles on the internet on how to go about it, so I won't bore anybody with what few details I do know. I'm collecting parts to build my own. Thus far I have a good working large York compressor and all the fittings, pressure regulator, safety pressure release valve, and an air tank. Still need a coalescing filter, pressure switch, air line, and of course a way to mount the compressor. Thinking of dropping the coin on serpentine clutch when the time comes.
Of course a 20 pound CO2 tank is a lot cheaper and easier. If you haven't, you might consider going that route just because it can be had now with min effort. I know some guys use them to power their air lockers in addition to airing up their tires after wheeling.