Audio Systems: 97 Lincoln Mark VIII radio, lincoln mark viii, series radios

Question
My radio is F7LF-18C815-AB. Was working fine until a cd wouldn't eject. Eventually got it out by lifting front edge, then it ejected right away. But now, it's stuck on one radio station and only the on-off/volume switch works. Can't change from FM to AM, can't change station, or bass, treble, fade, balance.  Have not put another cd in it since.  What happened and can it be fixed?  Have looked at many radios on ebay that look like they would work, but no way to know in advance.  Cannot find radio "chart" that explains differences between 815, 868, and 870 series radios, and cannot find interchangability list either. Any help greatly appreciated.

Answer
815 regular audio  some plugs are not the same
868 premium sound requires factory amplifier not JBL rear controls
870 also premium with sub woofer output  rear controls

e-mail oemautosound.com  they will help you getting the correct radio or make a plug for you