I just got my XM radio and have been looking for ways to install it not using the cig lighter, cell phone use that when needed. So i have been looking into the how-to for the sirius install. With the add-a-circuit i am going to guess you are pulling the radio fuse inserting the add-a-circuit in its place then installing the fuses. Besides the radio fuse what size is being installed. Also, I have the RBK radio with my I pod interface. I believe it has a cable for a sirius radio since that is what you would get if you bought it from the dealer. does anyone know what the wiring is for the interface and the radio. I want to run the audio directly into the radio some way or another, right know it is going into the aux channel of the interface. I have searched all over the net and in this forum for some answers and haven't really found what i am looking for. Also the 4 letter min. for the search is really a killer. Thanks in advance for the help.