GM Delco AM FM Stereo CB with microphone 1970's not working

Description

GM Delco AM FM Stereo with CB unit and microphone 1970's vintage
.
In untested used condition. Assume that it does not work.
Note written on top of radio unit....  "cuts out"
On off knob, tone adjustment, manual station select, all five presets, squelch knob, "RAD MON CB" and "SEL" knob all operate ...are not frozen.
AM FM selector slide is frozen and its outer button doe not stay in place.
Make sure is correct for your application. No returns.
See pics for best description.
Estate sale purchase.
May ship USPS instead of Fedex depending on destination address.