How does the output look with the composite?
The LCDs are fairly low res.. (800x600) so I think my best bet there would be to boot directly into Front Row. Front Row should look good at 800x600.

Also, I was thinking of getting a 150W Sine Wave inverter for the Mini, or do they make DC-DC power supplies for them... Hmmm.. I'll continue researching.

I have a spot in my dash underneath my Stereo head that would be perfect for a Mini. I'll draw up some diagrams, take some measurements and ponder a bit on this.