All of ours are done off the car however, nothing stopping you from pulling the lower shock bolt and dropping the arm down for easier accessability while on the car.
The problem you'll have is leverage, we use a lower shelf height on the press to prop up the shock end and everything is very "solid". With the arm hanging it will be kinda flexi...
We use an old 911 rear torsion bar (the big end) and a 10lb. Sledge. Bang, bang, out. Some "tools" just work.
Sometimes they come out with the inner 1/2 of the split race bearings. If this happens take a MAPP torch and heat the race and pry/tap it back and forth to get it off. If it is really stubborn I take a Dremel with a carbide wheel, notch it until you're close to the hub shaft (be careful here) and then use a cold chisel to finish it off. A couple whacks with the cold chisel and the race should break. Then it should be easy to get off.