Is it a Porsche mobile phone ? Does it have a handset which mounts on the side of the console ? The working parts of the Motorola version made for Porsche and with Porsche script on it, go in the right or left rear fender.
I have an '88 Jubilee/Celebration car which had one and was traded off when newer tech came on board. The place where it mounted is still visible, and I am looking for a set up as well to return the car to original. The place for the business end of the system, looked like it mounted in my car in the right rear fender well.
Sorry I cannot be of more help .........