Here's what I put in my C5. I had it done by a professional installer and just love it.
Metra Electronics - Chevrolet Corvette 1997-2004 Dash Panel (DP-3021B) Metra Dash Panels
Kenwood DDX6905S6.8" DVD Receiver with Bluetooth
Suction cup.
I glued a flat, round piece of plastic to the bottom of the cup holder to create a flat surface.
This a link to the model. I assume you were asking about the model of the cell phone holder vs the C5 model.
The suction sometime lets go and needs to be reset but overall it's a...