Here's my write-up, way back when, about this whole process:

http://www.type2.com/archive/type2/031996.html

From: "Craig Morton" <rangermorton1972@YAHOO.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Friday, June 15, 2007 7:46 PM
Subject: Drive Flange Oil Seal replacement

>I am trying to replace a leaking drive flange oil seal. I figured the two
>hurdles were getting the circlip off and getting the drive flange off its
>splined shaft. Both those operations went reasonably well and I thought I
>was down to an easy seal removal, parts cleanup, new seal replacement and
>then bolting it all back together. It was not to be. The old seal will not
>budge. The Bentley calls for a VW 681 seal removal tool. I have a Stanley
>screwdriver, some Craftsmen pliers, a hammer and my secret weapon ..... a
>spike with the end bent to a 90 degree angle. Well, none of the above tools
>has proven adequate. So is there a mechanic or a maniac out there with the
>correct backyard method of removing this stubborn seal?