Removing Volvo 940 radio
Remove the knobs by pulling them straight out
Knob removed
Remove the 'rings' behind the knobs by gently pulling them straight out
Locate the little locking clips and pull them inwards towards the center of the radio (one clip behind each knob). Use a small screwdriver or similar tool.
With clips pulled in, grab the radio and pull it out
Here you see one of the 'clips', simple springs, that hold the radio in place.