It depends how thorough you want to be. The York 210 has oil fill/drain bolts on its sides. I know in the 240s, sometimes the mounting bracket makes these holes inaccessible and you need to remove the compressor to get to them, but sometimes it doesn't. Once you have access you'd just put a siphon hose in and suck the old oil out and then fill with new oil.
Assuming you're flushing the rest of the system, the AC shop would then disconnect the compressor and dryer and flush the system with some chemical to purge the old oil from the lines and evaporator. You'd then install a new dryer. Dryers cost like $10 so don't cheap out on it, the old one will be useless by now.
I'd also replace the Tx valve. Also I'd replace every single o-ring in the entire system (it's not actually that hard).
At this point you should have a system that has no oil whatsoever in it. You can then put about 300ml into the York's crankcase and seal it up (put new o-ring on filler port bung). I used PAO68 oil but I wasn't able to get a definitive answer on whether I should use PAO68 or PAO100. I imagine either is okay.
Note that other AC systems often require you to add oil at various points around the system. For a York compressor, this isn't necessary, as the compressor will pick up some oil out of the sump and send it out the head port during normal operation, oiling the rest of the system automatically.
You can see here the fill port. Note there is a fill port on both sides of the compressor and you can use whichever is more convenient.