Installing a nokia hands free system in my 1991 300E, and have read about the Hirschmann antennas for the radio and cell phone which replaces the original radio antenna in the car. Can anyone advise on where they can be bought??? I have searched websites and don't seem to come up with an answer. I have a through the glass mountable antenna, but they say not to put it over the rear window defroster wires, that the phone will not work right. Any help/advise is greatly appreciated.

Thanks
Talons40