I added the Ford Sirius Radio Kit to my Thunderbird (also a 2004 with the "Sat" button). It is a seperate receiver and antenna. It is operated through your regular radio controls. When you press the "Sat" button, it is like changing from AM to FM or CD. The controls now operate the satelite recevier. Go to
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and take a lookat the Sirus reciever that works with your head unit (it is a Visteonproduct). The Visteon product description pdf can be downloaded from
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(this is for Sirius Radio). Go to
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and look at the bottom of the page foradditional information on the Visteon unit (including the operators andinstallation guides). Radiosandmore also sells XM solutions that willwork with your Ford head unit. You could just go aftermarket and repalce everthing. I have done this on one vehcile. And on a third I have an add on unit that goes through an RF modulator. Of the three, I like the Ford radio with the add-on kit the best.