Can I separate the CD player from below the NAV to install an aftermarket single din headunit and still keep NAV funtions? Will the fiber optic loop detect something missing and stop working? I'm leaving the rear door speakers for the NAV audio (which is rarely if ever used) and only replacing the fronts and possibly rear deck to run off the new head unit and amps. Don't ask, but it all makes sense after months of research. lol