You have got it down in the first two then you will need to take out the screws that hold side brackets that attach to the sides of the radio I beleive there are two and then the radio will slide out and if need be disconect the antenna, and wire connector.1. remove the control nobs for the ac/heater. they should just pull off.
2. I think there are some screws in the dash to remove the black center piece...i cannot remember, you'll have to look closely. If there are, I have mine removed and have not replaced them. The black center piece pulls out in one piece. at this point you should be able to access the radio.
I feel like I am missing something, it's been a couple years since I've had my dash apart. It really is simple, though, if you look around it's a no-brainer. there are no special tricks to taking it out.