Only jack up one side of your car, and the tranny fluid won't leak out, it will flow to the opposite side of the tranny. I have successfully changed both my axles on my 92 RS and didn't leak a drop either time. And yes the fluid level was full, lol, no trick answer here.

As far as the axle nut, just break it loose with a breaker bar before you remove your wheel. Now, the crankshaft bolt is another story...