I have all of mine (GRE 600, GTX 900, 857D, FT8900 and Magnum S9) all mounted in or on my Havis Shields radio console. The radios are bolted down inside it w the brains of the radios mounted under the rear seat. The wires all run under the carpet. The console is bolted down from inside the console to the body of the truck. There is absolutly no way those radios could get stolen with out a significant amount of time on their hands or with out makeing lots of noise or damage to the radios or vehicle.. they would have to steal the whole truck. And if they go as far as that, well they can keep it all.. i have 140k miles on it and i have full coverage insurance.
Depending on your next radio and size of it and also the make of your vehicle check out Havis Shields web site. They may have an application for your vehicle. If they do, give them the measurements to your radios and they can make it work for you.