I have a scion Pioneer t1807 radio in my 90 Landcruiser. It is "sat ready".I would like to add XM to it.Question1-is this unit compatible w/ both XM & Sirius ? I have a Pioneer gex p920xm XM receiver and would like to stay w/ XM as I have it in several other vehicles.Question 2- If compatible, is there an adaptor to hook up the square plug from the reciever to the back of the radio. The radio plugged directly into the trucks wiring. Where does sat cable hook up to radio?Thanks