2002 Chevy Trailblazer

I have a question, I hope someone can answer it. I wanna take out the factory radio, but I'm not sure how to do this. I was wonder does the peice around the radio just snap off, or are there some screws that I'm not seeing. The molding starts to come off around the radio, but when it gets up around the speed odomiter. It's kinda hard, I don't wanna snap anything off..so if some could me out I would appreciate it...thanks..