I have the dealer installed Sirius unit and it works great. However, my antenna is currently located on the dash and I have good reception there. I'am inquiring with many sources concerning the roof top mounted antenna and if there is already a wire run from the factory for the satrad. So far no one knows the answer. You can go to the following web site and check out what they have and the one kit is the one I got from the dealer. Check it out. oem-auto-accessory.com