I'm not sure I understand the question....which won't surprise some people, but if your asking what I think you are here goes.
If the gaaket it on the rear/backside of the housing then just simply take the bolts out and replace it.
If you need to replace the front gasket then thats a different story. Here you have to pull the rear cover. Then push in on the axles and take the little "horseshoes" off the ends of the axle so you can pull the axles out. Don't pull the axles out and leave them laying on the axle seals because it will cause them to start leaking. Now would be a good time to replace them.
Once the axles are out, take the nuts/bolts out around the front of the "pumpkin". Once you get that done get you some one to help hold or pick it up and pull it straight out. A engine puller works good.
Oh,there are a couple of "spider gears" that will "fall down" but don't get excited. Once the driveshaft/pumpkin is put back in you can put those little spider gears back in from the rear of the housing.
Now, if this is not what your looking for I needed to practice my typing skills anyway
