Difficulty depends on how good you are with computers, and how seamlessly you want it to operate. If using Itunes or WMP is all you need to do, then its just a matter of making it run on 12v. If you want to have a menu driven system, that looks more like a high end stereo, and if you want things like satellite radio, it can be more difficult. And, if you want this thing to power up quickly and automatically, its another step.

I've had two different systems. The first, I built myself, using Frodoplayer, which is a really slick, skinable, menu driven interface for MP3, DVD, back up camera, XM, and some others. Oh yeah, its free. While this system worked well, my goal was to have it be as simple as any commercial touchscreen type in dash. I ended up writing lots of custom macros, and it still wasn't perfect. Start up time was also a little too long...about 90 seconds. All the parts you'd need are on MP3car.com.

Now, I'm using Drivesoft, and its just about perfect. Works just like an indash, and will boot up within about 30 seconds. This system is designed to be an in car system and has a custom bios, as well as some custom power tweaks on the USB system to make it more stable. Its pricey, but its very, very good. It can also be installed and used with only minimal computer knowledge.

Now, I don't know how to do any of this with a Mac...these are all for PC's.

As for getting the monitor into the dash, that just takes time, bondo, and some technique. Not tough to do, but sometimes tough to make look right.

Toby