well, i wanted to do the same thing in my '03.
i bought, what i was told, an '05 radio module.
but, if u read my other thread concerning "Sirius
Issues," u'll see that even though it may have been
an '05, that doesn't necessarily mean it has Sirius
Software. my only advice is, if ur gonna buy one,
make sure whoever sells it to u will accept returns.

i was told that BMW used the same part #'s for
the radio modules from 2001-2005. hopefully, ur
luck will be better than mine.

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