You can get the 6WB part for about 2k (not cheap). You'll also need coding - but I understood (see wd's earlier posts in this thread) that the 6WB part prevents some of the additional HUD coding from working (e.g. lane change in HUD).
There's some info in the F10 forums about what's involved (don't know how much of this info is applicable to F15 but might be useful background info):
http://www.bimmerfest.com/forums/sho...d.php?t=666531