Got a like-new 2001 Monte Carlo LS. Interior has the original AM-FM-CD combo. Is it possible to upgrade to either an OEM or aftermarket stereo that has bluetooth and mp3 and will maintain a factory fit? I don't wanna upgrade the original equipment unless I can do it "without" modifications to the dash or wiring, just in case I ever want to reinstall the OEM radio. Does anyone know of a unit that can achieve this?

Thanks in advance for any feedback.

Michael