heater core replacement

[mojeepn]

I'm replacing it right now, and I've been told that the whole dash needs to come out. I've got the bottom grey part out, and there's a bunch of black plastic down there that I assume has to come out. However, I'm not feeling like these screws I"m taking out are actually loosening everything up. Help?

 

[mojeepn]

So now I"ve got all but two screws out of the black plastic pieces, but I can't see how to get them out. They are all the way underneath the dash, and they have to come out for me to get where I need to go. How do I get the top grey part of the dash off?