Power button removal on a PM G5 mod. 11.2 Late 2005

Hi!

How do I remove the power button attached on the logic board? I have unscrewed the two small black phillips screwes attached to the tiny logic board to the power button, but there are also two other tiny screwes on the power button that must be removed. Unfortunately I am not able to remeve these two screwes, what sort of screwes are these? Any suggestion how to fix this?