I have a question about the shark fine on my 05 325i with assist. Can i use this shark fin as an antenna for more things than just assist? i'm about to retrofit nav into my car, and it'd be cool if i could just use this thing instead of adding yet another antenna to my car. and how about sirius? i had the dealer install sirius for me (i wish i would have done it myself), and they mounted a magnetic antenna on the trunk lid. i was expecting it to be tied into the shark fin, but maybe this isn't possible?