I got in contact with Bimmernav.com and they have Bluetooth integration for my car for $725. Navigation will be $4000. Unfortunately it doesn't look like I'm going to have any luck at all with a factory Sirius solution, however. BMW USA insists that it isn't possible (which I don't believe -- it's possible
but it's an issue of how worthwhile it is), my BMW center isn't willing to perform the necessary labor because they're worried about what would happen if they messed up (not the most encouraging thing to hear from your BMW center), and Bimmernav offers no solution for Sirius.
I guess if I want Sirius I'm going to have to go the plug-and-play route which I really didn't want to have to do.
Has anyone installed the Bluetooth kit from Bimmernav? How involved is it? I used to do aftermarket car work but I've obviously never used/installed this particular system.