Hey Phil, I just bought the frictions discs from him, which were about $225 I think, the bearings and races I got from Canadian Bearing (after market, but the exact bearings that bmw uses) for about $35cdn, the seals I got OEM, for about $50 think. I ended up just switching the lsd hub into my open diff because the teeth on the pinnion gear were chipped pretty bad, and I didnt want to mess with setting up the pinnion depth (according to Koala, thats really the only hard part). Only took an hour or two to get everything setup, and I never had to remove the old diff from the car. The diff works great now, no chatter, and grabs perfect. I have probably put 4000k on in since the rebuild with no problems, and a bunch of auto-x days. So much more fun in the corners than the open diff, and faster too!!
If you need any more info, just let me know!! I was going to write a how to, with some pics, but I got a little excited when the discs came in and forgot the camera at home. I still have the internals from the open diff if anyone needs them.
Cris