Yeah, you 'could', but you'd probably have to turn one off when u wanted to transmit on the other. A better way perhaps wou be to either get a DUAL Watch rig, or a scanning transceiver (like a ham rig, or the new Cobra 29 LE), etc.
I don't know if they still make them, but there used to be something known as a CB convertor, which plugged into your car radio's antenna connection, and allowed your car stereo, when tuned to the AM broadcast band, to function as a CB receiver With one of those, you could listen to a particular CB channel on your car stereo, and the other CB channel on your CB transceiver. However, again, once you wanted to TRANSMIT, you'd have to disable or switch off the stereo convertor, or face overload