I just had a double Din Navigation installed to replace the junk factory radio. I had my standard stereo shop say it couldn't be done. I got a second opinion and the guy said he'd have it done in a couple hours. It looks like a factory install! I couldn't be happier. It's nice to have the Nav, Bluetooth, XM, DVD and IPOD all in the same unit. I also added an Aux input for the TV so whatever's being played in the back will play up front if desired. I'd say it's my best add-on.
I also installed an indoor/Outdoor temp sensor where the cigarette lighter was originally located.
Also removed the bulky Tube TV and installed a Jensen 26" LCD. It fits perfectly in the space. I used an articulating arm for more viewing options. It worked out pretty slick as well. I was really concerned about how to mount it solidly in the cabinet space. In the end, it's rock solid and frees up space behind the TV for more storage. I'll post photo's of that as well.
Long View:
Back of the set... I wanted a more secure mount, so used all eight mounting screws to mount the TV to a 3/4" board, then mounted the TV to the bracket with about 20 wood screws.
Cabinet mount: I placed hardwood boards on the top and bottom of the cabinet, then doubled up 3/4" boards, screwed and glued for strength. Made brackets out of aluminum angle stock (Lowes). Bolted the brackets to the vertical piece, then screwed top and bottoms, front and rear. I think I would rip out the cabinets before the mount comes loose. Overall, I'm very pleased with the way it came out.