How to take out my car stereo?

So my friend and I are trying to hook up my subs and amp to my car. But when we were trying to get out the stereo part, we took off the black surrounding plastic part. We took a knife and were just trying to pry out the stereo, but something is getting stuck and it isnt just sliding. Any tips??? Please let me know what i should do and if there is something blocking it etc!How to take out my car stereo?
there are some little sticky out triangular bits of metal on each side of the radio, when the radio is pushed in to the metal surround, the sticky out bits are there to stop the radio being pulled back out, a bit like a barb on a fish hook,



what you normally get with a radio is 2 thin flat strips of metal which help you flatten out the "barbed" bits of metal, after putting both strips down each side, you have to wiggle the radio from side to side, bringing the radio forward bit by bit, it will eventually come out,



you can do the same with 2 thin knives, you can do the same with one knife, but you have to keep swapping it from side to side, bringing the radio forward bit by bit.



Good luck !How to take out my car stereo?
Use a baseball bat and beat that **** out!