OK, Here's what I've got:
-2003 X5 3.0 w/ NAV v.29
-Radio (factory) BM53 with flat pins
-Software Version 28-02-81
-Sirius Receiver 65120416377

I used the audio extension cables and BMW antenna... everything fit together like a snap but when I press the MODE button on my radio the SIRIUS option does not show????

Any suggestions? Have I missed something? I tried to follow all of the previous posts to be sure I did not skip and details and I'm at a loss.