Dont apologize. Thats a PHAT reference!
Of course you wont find someone who has installed the relatively BRAND new mac mini, into your obscure vehicle...carputers are highly personal.
TV tuner (worthless, why do you want that while driving...? then again, you might!)
touchpad (not needed with a touchscreen)
Dont look at your project so much as a Mac into an Acura MDX, think of it as a Mac in a car and youll be much better off at first.
When you are done with the hardware part of the installation then you can make it more personal by adding things specific to your setup.
There are no completed front ends, make one if you like but I think offering help to some of the already begun ones, might be better.