I'm in the car business (same Ford store for 7 years), and trying to find the Sirius module for the THX/NAV seems to have been harder then finding the Holy Grail, the Loch Ness Monster, and Bigfoot. After months of searching I FOUND IT! What a difference! The FM2 buttons becomes SAT, and FM1 now cyclces to FM2. The display shows the song title/artist/channel. You can search by catagory, and you have 3 sets of 6 presets SAT1/2/3. Not to mention the sound quality of full digital sound!