It was the interior that drew me in to the 2013. My 2010 f150 Harley was pretty snazzy and I'd say my ram steps it up a notch. The screen is the best out there...
I would think it could be done but it would be costly. How to integrate the sensors and the EVIC would be the difficult part. Not sure if the functions of the pre-2013 EVIC are the same as the new one and that might dictate what is possible without codes being thrown.
Another consideration is security system, I know some factory radios can't simply be swapped from one car to the next, not sure if the screens behave in the same fashion.
Probably cheaper to buy a 13