You do not need to support the engine, just get the car up on stands to remove the front wheels. Air tools always help but are not required for this. I did loosen the subframe bolts a bit to drop the rear of the subframe 3/4-1" to give a little more access room, as I was told it would help. Only did it once so I can't tell you if it was easier than not doing it. The subframe bolts are very long and have a long engagement with the nuts so you have some room to drop it slightly.
The worst part of the job, by far, is accessing the PS hydraulic fittings on the rack. There is very little room to swing a wrench to get them off, and it is even harder to get them lined up correctly so you can get the threads started when putting them back on the new rack. The seals that are in the fittings make them very hard to turn by hand to get them started, which adds to the fun. I think I did mine over parts of 2 days. One to remove, wait for new rack to come in, trade-in the core and get new one, then part of a day to reinstall.
Don't forget to keep the 2 rack attachment nuts and the outer tie rods, as the new rack does not come with them (mine didn't). Autozone - was about $215ish for a Cardone reman rack. It is good to have your old rack there to compare with the new one and make sure it is the correct one.
Helsm manual was very complete and easy to follow.