post some pics! i have a 00 sierra that i've been wanting to put a computer in. I too want to keep my aftermarket cd player. i was actually thinking of mounting the screen where you want to move your cd player, but if yours turns out well, maybe i'll change my mind.
my biggest fear is all the fiberglass/bondo work i would have to do, and i've never done any of it. i was gonna order a second center console bezel in case i messed mine up too bad.
anyway, good luck with your install.