With multiple drive belts, use to install compressors on top of the engine, easy to work on, with a single drive belt, mount them at the bottom, around here, exposed to road salt.
R-134a is a PITA to work on, should completely dry out the system, install a new dryer, draw a deep micron vacuum and inject that women's facial cream into one of the ports. Any moisture in the system forms an acid that will eat your system away.
On these types of vehicle with no front room to work with, been able to remove the compressor mounts, very carefully and bend the front end of the compressor to work on the clutch.most have neoprene hoses, look first and tie it up with wires.
Typically with just the clutch going back a few years, was only 50 bucks more to get the entire compressor with it. Really nail you for just the clutch.
Some use a snap ring to hold the dual roll ball bearing in place, some are pressed in, worse are peened in. Once the bearing is in hand, can snap off the seals from the outside, clean off all the old dried up grease, check for any pits and pack it full with Wolf's high temperature Red bearing grease, will last forever.
Best cages are revited, next best, spot welded, cheap crap from China, plastic, pitch those.
Plate may be pressed on, better with a large nut should be adjusted some with shims for about 8 mils of clearance. Magnetic force decreases by the square of the distance, few thousands more, won't pull in.
Another PITA is the clutch magentic coil, most pull 4 amps, more, could have shorted turns.
Back in 1956, York compressors were used with an oil sump, most had a sight glass to check the oil level, later they were mixing the mineral oil with the refrigerant, cheaper, but more like a 2 cycle engine compared with a four. Even your refrigerator has an oil sump, they last for years. But in automotive can loose just the oil with explosed seals, that's when the compressor seizes.
Prices going way up on this crap, quality way down.