I did this before, without a lift. It's not something I would ever wish on anyone for punishment.
It was an '88
Trans Am. I wanted to swap from an auto to a 5 speed, so I did

.
Basically, it involved some SERIOUS stupid order of events:
1) Drive the car up on to a home made car trough (basically, I took a load of 8" cinder blocks and two wide on each side and three high - 24" of working room!).
2) Place blocks on all four wheels.
3) Place 8 (yes, eight) jackstands at various points, yanno, "just in case"
4) Placed 4 jacks and put them under slight tension, so they'd be the first things to catch.
5) Drop the current
tranny etc. using two additional jacks, because while I could benchpress that thing in and out of place, I wasn't about to try (considering I wouldn't have been able to turn a wrench and all)!
6) Bolt in new components in a similar fashion using a variety of jacks.
I found out about 2 weeks after I did that, that the local garage w/ a lift would've let me use it for free. D'oh!
I'd highly, HIGHLY, reccommend that you find a place that will let you use their lift, or have at least two buddies around and some means of having a ton of room under there. I would NOT do it my way ever again. Let's just say the words "young" and "stupid" were pretty serious factors, eh?