http://www.taolife.com/tao-main.html
First thing I found as I read into the product is you need nothing basically!
The Tao xm2go has built in FM modulator apparently so will transmit to the nearest receiver (i.e. your OEM radio!) - it even has selectable frequencies so you can pick one that is "free" and works well with your unit. No wires necessary. Nice feature!
There are other options available like the typical cassette adapter modulator but I'm not crazy about those!
Here's the full manual on-line. which covers some of the methods.
However, you always lose something in fidelity with a modulator, so hard-wire solution is better.
You can start with an auxiliary adapter like the
Blitzsafe Hon/Alp V1.d - there are several other manufacturers available but the Blitz is the only one (that I know of) that can still retain use of the CDChanger
as well as adding an auxiliary input since that is a concern.
Then you interface it very similarly to an iPod - get an adapter for ear-piece to RCA outputs (to plug into the Blitzsafe adapter) for basic connection to play through the head & OEM audio amp/speakers. It should have excellent fidelity (well, comparable to OEM CD audio).
I see that there are various other enhancements you can then add as desired for improved user friendliness & maybe even performance. Unfortunately nothing as integrated as some of the products available for iPod integration given its abundant popularity in the market, relative to this unit.
e.g. Power adapter; cradle (or vent mount!); maybe most beneficial might be vehicle antenna.
You wouldn't have to buy the earphone/RCA cable adapter from tao (even RadioCrap has those!); the other parts, probably. If it were me, I would probably cut off the cig lighter power adapter & hard wire it since you would inside console anyway to plug in the Blitzsafe; then have my antenna, power & ear-piece adapter outlet in convenient location where I would mount the XM controller.
Not sure how you feel about it, but you could conceivably have the cables exit the vent grilles & tie into the unit using the vent mount. I also have an extra coin tray that you can have, if you'd like to see if you can use that to inegrate the mount and drill a hole to have those cables come through it also - that way you could play with it & retain your original.
.