Ive got an appointment this Saturday (11/26/16) at a local car audio shop to install a Rockford Fosgate P3D4 - 12 (12" woofer) in a custom ported box to be powered by a Rockford Fosgate R500X1D Amp. Going to keep the stock infotainment unit at this time. I would like to upgrade the infotainment unit but don't want any issues with the car being able to communicate with the unit. Has anyone upgraded the infotainment unit and ran into any issues? I've got an ex-l coupe.