Hello. I have a 2000 LS with the 6 disc CD changer. I want to do an upgrade on the stereo head unit. I want to get a new head unit and if possible retain the steering wheel controls. Don't really need the disc changer. What kind of problems/glitches should I be aware of and are there any particular brands/models that are known to be compatible with the LS. Bluetooth capability is a necessity. Any suggestions?