ITnate3,
I just put one in my '02 with the Alpine in dash 6 disc changer for my XM a couple of weeks ago. I actually found the best deal on the apatper from Crutfield. They sell USA Spec brand, and I found a Crutchfield coupon online for $10.00 off and free freight. This unit actually gives you two pairs of RCA inputs, in case you want to add an iPOD or something. I had always considered them high price, but they were actually competitive even without the coupon. They also send you detailed instructions. Their price was $59.95 I think, and with the discount it was only $49.95. I just searched online and couldn't find the coupon code, but if you call them they might be of some help. I also ordered the VSM mount, which was a tight fit, but works "pretty sweet". Actually the adapter was a tight fit as well. As Quick said, your head unit automatically knows that you have the harness installed and allows you to toggle to the input with the "Media" buttom on your steering wheel. Good luck!