I may not be able to describe this well, but they are held in with the one screw. Mine came out without any drama, but they kinda swing out at the screw side. Those two slots on the opposite side should come apart without much effort, but it sounds like that's not your experience. You could try pushing in from the outside at the screw edge. You could also try lubing the slots/pivots with some dish soap.
Hope this helps,
Tom