Ive done it on jackstands, but you have to get that thing sky high to make it easy enough to get under there. Here is a picture that shows what I did. I also used some truck wheels under each tire so that incase for whatever reason it came off the jacks it would land on the wheels. (it was very sturdy but it was just a precaution).
The fun part is like you said getting the clutch plate aligned with the shaft of the transmission. When you buy the Zspeed it comes with the alignment tool, just make sure it is a straight as you can possibly get it while installing. The first 2 times I did the clutch (Ive actually done it 3 times now) it was a straight shot to mount up the trans. The 3rd time however it took about an hour of fighting with it to get it to seat.
Whatever you do do not use the bell housing bolts to suck in the bell housing, you should be able to push it together with your hands, if not something isnt right. Its pretty easy to do IMO, it just takes some time and patience.
Hope this helps.