My experience is there is no need to get a Bosch antenna. A complete, new $60 (approx, depending on features) Harada power antenna will work just as well. I put one on my 85 4k and the only adjustment I had to make was the size of the hole. These antennas come standard on Toyotas and Hondas, so they should be allright. Of course, if you feel the need for Teutonic parts, you can pay a lot more.