When I replaced my Diff., I used this tutorial as a guide. It also outlines the axle shafts as well in the first steps.
PeachPartsWiki: Replacing the Differential
You will probably find your answer in here. There are 4 studs/nuts that hold the diff to the subframe. You need the car up in the air on jack stands and you need to be able to move the subframe up and down once you remove the rear diff. mount.
Being able to move the subframe up and down allows you the room to "get the axles out".