How to remove the shell on a 2-10-2

[jalajoie]

I tried to remove the shell on a Bachmann USRA 2-10-2 but someting seem to hold it near the firebox. So far I removed the 3 visible screw the one under the cylinder and 2 under the firebox.

When I try to lift up the shell something seems to hold it in the back near the firebox.

Thanks in advance

Jack W.