Ford Expedition Forum : “How do i disassemble the driver side turn signal mirror?”

How do i disassemble the driver side turn signal mirror?

My drivers side turn signal shows signs of water leakage inside it. I want to disassemble it, clean it, and check it's gasket. I can only find 1 small t10 screw up under the edge of the signal lens, but it still won't come out. I tried to find a repair manual at the parts store, but they tell me there's none available for my 04 expy.
Any help would be greatly appreciated!