I have an '09 GTS that has been modded before I got ahold of it, so I'm not sure what the "damage" is, but someone replaced the RF stereo head unit with an AM touch screen head unit, and I would really like to get an OEM Nav head unit. Before I buy one that I know is compatible with my year model, I'm wondering if anyone has installed a '14+ Nav head unit in previous models. All of my research indicates that it is not compatible, but does not indicate why (everything else in the stereo bay is compatible). If it is compatible, does anyone have any leads on a '14+ Nav head unit, and if not, does anyone have any leads on an '08-'14 Nav head unit? I am also looking for the subwoofer (enclosure specifically) for the sedan model. The goofs who owned the car before me removed the sub and enclosure, and if they replaced it with anything, they took it with them