I installed Sirius in my '03 4runner the other day. I used the USA-Spec auxiliary box. It has two sets of inputs, so you can also have a direct connection for an I-pod. You plug the USA-Spec box into the CD changer port on the back of your head unit and run a RCA-to-mini jack line from the USA box to your satellite radio. You will still be able to use the steering wheel controls for volume on the satellite radio and to toggle between sources (am,fm,cd,cd-1,cd-2). If you have an outboard cd changer, you would lose the changer with this set-up. I have the single disc JBL system, so it was a a no brainer. I mounted the USA box in the upper glove box area to give passengers easy access to the additional I-pod cable.