How do i remove the factory stereo from a 2005 Chevrolet Equinox?

I'm buying my first car and it is going to be a 2005 Chevrolet Equinox. I plan on replacing the factory stereo with a Pioneer AVIC Z3 Navigation system.

Can someone give me step by step instructions on how to remove the factory stereo?
Diagrams would be very helpful also.

Thanks a lot.