GCN Controller Disassembly! HELP!

[Inunah]

My sister's Gamecube Controller has a button on it that no longer springs back up, so we decided to open it up and fix the problem ourselves, but now we can't pull the motherboard from the front of the controller! Help!

The controller is a Madkatz. Not the ones with the small buttons. The ones where the controller was a bit fat.

 

[Inunah]

Okay, we got one side of the motherboard up, but the side with the z button refuses to come out.