hi, im looking for 2004 and up cd changers for a 2006 f-150. i only got the basic audio package, it only has a cd changer but i want a 6 cd changer, it can be mp3 capable also. also i want to buy a factory dvd unit, but the problem is my f-150 didnt come with the overhead accessory rail. would it be possible to add it on? thanks