Does the factory XM radio connection work with an aftermarket headunit?

and the second question, does an aftermarket XM radio connection work with the stock wiring that is done to the trunk.

I have an 04' so the car is wired for XM, just wondering about my options.

Thanks

 

Alpine Head Unit: $200
XM hardware needed: $100

I reckon this should be in the electronics forum...

 

Addendum:

Modifry's DCU interface: $90

Not having to go to the dealer for audio upgrade: Priceless

 

I'm still looking into this but, I read somewhere that there is an S2000 adapter made by Alpine for the European units that may work here. I want to try to get one of those since it will probably be cheaper/work better...