My understanding is that if you want the mirror-mounted type that comes on the 330cic then you have to get the same rectangular mirror -- not strictly a factory upgrade, just something you arrange with your parts dept. I picked up a little doodad from Radio Shack that fits nicely in the cupholder -- it's almost small enough and light enough to put on your keychain, though it'll be banging around below the steering wheel with all those g-forces
pw