How do I take the factory radio out of a GP?
 

I am installing an aftermarket deck in my friends 2004 pontiac grand prix and then installing two 12" subs. I have only seen the inside once and I wanted to make sure that whenever I started to install the deck that I could get the factory radio out.
Im not sure whether I would have to remove the dash or not. If I do need to remove the dash could some one tell me how to remove it.
Thanks alot