I just purchased this for my 1970 Buick GS455,
http://www.ebay.com/itm/CUSTOM-AUTOSOUND-Secret-Audio-SST-Hidden-Stereo?item=170394676153&cmd=ViewItem&_trksid=p5197.m7&_trkparms=algo%3DLVI%26itu%3DUCI%26otn%3D1%26po%3DLVI%26ps%3D63%26clkid%3D8376145437774745048
You can hide the main unit anywhere, and control the unit with the small LCD panel, or with the RF remote. Look at all the expansion, and connection possibilities this unit has. They didn't forget anything. This may not be what you have in mind, but it is ideal for me, as I want to leave the dash stock looking with the original AM radio. I will hide the unit under my seat, and the LCD controller in my center console.
_________________
98 Riviera SC3800 All stock except gutted air box.
1970 Buick GS455 Stage1, TSP built 470BBB, 602HP/589TQ
Best MPH, 116.06 MPH, Best ET, 11.54
https://www.youtube.com/watch?v=UHCda-t_Jls
https://www.youtube.com/watch?v=sfT2tEO4XcU