I just picked up a 2005 Black LT. It has the Bose + Navi option however I am getting the "No Nav Disc" message. I only see 1 CD slot on the head unit. My question is, can I only either listen to an Audio CD, or USE the Navigation? Or is there hidden CD slot somewhere else for the Nav disc. I called 2 dealerships, searched the forums, and I do not have the Navi manual. It seems very stupid to me that you could only do one or the other, seeing as on any road trip you would usually listen to a CD while using Navigation. If this is the case I am not going to pay $200 for a Nav disc, I would go get a Garmin for $100. I love my truck I'm just getting frusterated that the dealership tells me "I don't know, look it up online" Any help would be appreciated.