Ok, I just got the F90-BT installed in our '06 SS Trailblazer. Everything works for the most part, although I can't get the mute and the source up/down buttons to work on the steering wheel. (I did the hardware parking break hack) I'm assuming because there is no mute control now. I also ordered the GEX-P920XM so I can have my XM radio again. No one has it, they're all back ordered. Does anyone have a kit to use the GM factory XM radio with the Pioneer unit? I also prefer the GM XM radio antenna over some little magnetic or stuck on with wires draped around.

there is no way to use the factory XM module with an aftermarket head unit, however if you mount the pioneer XM tuner where the factory is then you can use the factory antenna, not sure about the trailblazer but a lot of GM's have the tuner behind the glovebox (suburban)