Use a spatula or something similar and pry up the edge facing the inside of the car (the side away from the windshield). It'll pop out fairly easily. Then just disconnect the clips from the speaker and set it back in. Bonus TIP: If you've had any issues with rattles on the dash sometimes it's that center speaker..I added some weather stripping to stop that from rattling while I had it out.
WOW That was quick. Thanks, I will do that this evening. I heard it improves the sound quality a bit not using it.