dontcallmejeff

I posted this in the Miata discussion, but I thought I would post here also. I'm about to get the 900bt installed and purchased a Sirius interface. But the installer is saying that the current Sirius receiver only works with the Miata head unit and I will need to purchase a new reciever, is this correct. Also does $250 sound like a fair price for the install, I'm in St Louis. Thanks John