change the phone?

My 99 C280 has a Motorola Microtac phone. I am assuming all the specific electronics is in the phone, and not the car, as you can disconnect the phone and carry it around and it is functional standalone. My problem is that this is my wife's car and she insists on the Motorola Star Tac, which of course is much smaller. The problem is that the Star Tac and the MicroTac use different cable connectors. Does anyone know how to get a different cable for a Star Tac to connect it to the factory unit?