Go to a car parts store and get the Ford radio removal tools. It's two U-shaped rods that fit into those 4 holes. You put in the rods, tip them slightly outwards, then use them to pull the radio or whatever towards you.
You could cheat by using 4 nails or small screwdrivers, but the danger is if you go in too far, you risk bending the clips, making it extremely difficult to remove. The rods usually only go in so far.