It's not something that's really worth a DIY. When I did it it was $300 to have them re-bushed, and at that price having it done properly in factory is totally worth it.
Doing a quick search I found this--no idea if this guy is still active, though.
http://forums.pelicanparts.com/porsche-911-technical-forum/562566-bilstein-strut-play-safty-issue.html#post5544544