how do I remove rear light cover

[sring]

I have removed the two screws that hold cover, but I can't seem to get this cover off... What else needs to be done to replace the rear brake light bulb?

Any help would be great..
Thanks
Sharon

[nick0750]

REMOVAL
Disconnect and isolate the battery negative cable.
Open liftgate, remove two hex head bolts in inner D-pillar, Rotate lamp outboard away from vehicle to remove tail lamp forward stud from grommet.
Disconnect electrical connector.
If replacing the tail lamp unit, transfer lamps to new unit.