subwoofer

Can someone please tell me how to remove the plastic back trim panel to gain access to the subwoofer housing in a 2001 Tahoe?

I'm finally posting some pics of my install. I'm still not totally done with the grille for the back of the console. I'll post pics when I get that done. I did not have Bose in my Tahoe, and the non-Bose speakers suck even worse than the Bose speakers. I wanted to keep a stock look and add...