This post is only to show off a bit. ;-) It's only from the advice and assistance of the guys/gals on this board that I was able to do this... so thanks to all of you.
First, the car, a 2003 Mazda MX-5 Miata LS.
I wanted to install a Xenarc 700TSV into the dash, along with a slot-load CD/DVD drive. The double-din slot wasn't big enough for both, so I knew I'd have to lower the display to allow enough room at the top for the CD insert slot. That meant removing the buttons on the Xenarc. My idea was to build a wooden box, disassemble the Xenarc, and attach the circuit board, laying horizontally, to the bottom of the box. Here's the box, built to the exact dimensions of the OEM head-unit.
Here's a test-fit into the dash.
Starting the bondo work, I left about 1/4" space between the bottom of the factory shroud (silver) and the top of the now-chopped-down Xenarc bezel. My plan was to cut a slit for feeding CD's, with the drive itself mounted to a shelf in the wooden box, about 1/2" behind the screen.
However, after cutting the slit, filling it, sanding and trying again and again, I could never manage to dremel out a straight line! I finally gave in to my impatience, scrapped the built-in CD/DVD idea, filled the whole thing in and applied the heavy-fill primer (several coats and sanding in-between).
Finally, as I couldn't find a silver paint to match at AutoZone, I opted to go with a flat black acrylic enamel that turned out better than I thought.
Then came the easy part... attaching the screen to the new bezel, fitting the circuit board to the wooden box, and mounting the whole thing into the dash.
I did miss one important thing. I meant to drill a small hole to relocate the IR receiver of the Xenarc, but forgot all about it. So, this Spring when the weather is nicer, I'll do that and try cutting out the CD slot again.
Again, thanks to everyone who's submitted advice and tutorials, as they were invaluable!
-Meta