Hello,
I love any project that involves a car and PC.. however after coming from owning 3 cars all with CarPCs to owning my 370z with an Android tablet.. mounting a tablet in our car is well, just AMAZING. i love every bit of it. the music player is nice, 4g tablet is even nicer! Google Maps Navigation is prob the best navigation software out there... and its FREE!
Don't get me wrong im excited for your project as i still love carpcs, but the tablet is just way more reliable, stable, ease of use, multi touch, and i got mine for under 200 dollars.
My buddy and i fabbed in the cubby hole, a case of beers was plenty for his help, lol
Here is a pic of what im talking about