Here's a little write up and, more importantly, a picture (click on the little blue button) in the link below for replacing swingaxle seals.
The Idiot's guide doesn't say much about it, but I've read that the Bentley has a picture and whatnot. Might want to use that instead.
Kermit sells a seal replacement kit that's pretty reasonable. There are two paper gaskets, but don't panic. Only one is needed for Type 1's. Both are needed for Type 2's. Everything came apart pretty easily. Just needed to clean everything up thoroughly and used some emery cloth to clean some rust off the seal surface. There are supposed to be two o-rings in there too. Keep looking they aren't obvious.
Also, jack up the swing axle (not just the car) high enough that it doesn't leak and check your trans fluid level when done installing the seals. As long as you're already busting your knuckles, it might not be a bad time to change out the trans fluid, and, maybe even the rear wheel bearing.
Not for nothing but oil soaked brake shoes won't slow your baby down very much so they may need to be replaced too.
http://www.nls.net/mp/volks/htm/swgaxle.htmGood luck.