Here is what we did for my son's 99 323. We ditched his radio for a 03 (I think one needs a 6/03 or 9/03 business cd radio, We bought it on ebay for...
I suggest you post and search in "x5world.com" That forum is the best for bmw nav info.They have everything, its amazing.
Have you checked into the DICE adaptor? It seems to be a "son of ICE" deal but it is very popular with the e46fanatics crowd. a site sponsor...
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