if i were to do this at home i have a few questions.

1. Does the whole motor/trans have to come out to do this or can i unbolt the crossmember, exhaust, driveshaft, linkage etc. and drop it down from underneath using a floor jack (without a lift)?
2. are there any special tools required.
3. any pitfalls i may encounter doing this?

The cars still driving now but i just want to make sure i know whats going on if it eventually dies.

Also is there any link between the transmission problems and the higher water temps and lower MPG?