This guy use the OEM 16:9 Screen but is connected to a computer (only difference would be that you use a Xenarc as a touch-screen):
http://www.car-amp.de/
With a Car-Pc you can add navi, dvd, tv almost everything... but you will need to do some configuration and have some skills to make everything work properly and smooth.
http://www.cartft.com/carpc/catalog