a mini-itx motherboard with minimal accessories will easily fit underneath the drivers seat. I had to remove some of the foam padding for mine underneath the carpet. I also replaced the metal rod that's for the seat adjustment with a thick gauge metal wire, and hooked it thru loops attached further up into the seat, that was a piece of cake. It allowed for ALOT more clearance then stock.

My setup has been for the past few years an EPIA M10000, with a PCI Radeon riser'd parallel to the motherboard, sitting atop. Whenever I need cd/dvd access I hookup an external USB cd rom. Too much vibration in the car to use this while driving so I didn't find it worth the effort to integrate further.

Living in Texas, I opted not to cover up my front AC vents which you would have to do for a 8" monitor. A 7" you probably could get away with refabricating those vents just to be much thinner. This was an option I toyed with for a while. If you decide to fab the monitor in your dash, avoid the fiberglass/bondo combo as you might run into expand/contraction issues with the dashes plastic. I would recommend an ABS mix. You can investigate this solution on the www.mp3car.com forums.

I installed my monitor where the 6-disc was. I purchased an extra dash piece of that area around the 6-disc, and a 2nd trim piece that goes around that area. I then created a custom enclosure around that trim piece, based from a foam carving I made. Now this was done with fiberglass and bondo. The original LCD was mounted inside the fabbed enclosure. The whole piece utilizes the existing clips of the existing trim piece, so it can be detached/attached easily.

I've since replaced my shifter with a shorter, smaller round razo so the display isn't obstructed. And the viewing angle is perfect from the drivers seat, and can't be viewed by passerbys.