The clutch fried on my old A/C compressor so I purchased a used one and will be installing it in the near future. Right now my refrigerant is completely empty and I'm just wondering what other precautions should I take while swapping out the compressors? Thanks.

 

If you're sure that the freon is all gone, then I would just pick up some new o-ring for the low/hi side connections to the AC comp.

Also, it may be a good idea to have a shop refill the freon, so they can also suck out any possible air that's still in the system.