Remove Front screen?

Morning, An 03 CRV Sat Nav started making a noise and the DVD disc would not eject, finally got it out ( bit scratched though ) and I have taken the unit out.
There are two screws either side of the Sat Nav and when removed the bottom section does move in and out of the unit.
However the top remains firm, I notice that there are two metal tags at the top of the sides just above where the mounting brackets secure, do you have to " manipulate " these to release the top of the unit or do you have to dismantle further components.
I just want to have a look inside where the DVD disc to see why the disc would not eject, I did run a cleaner disc through it a few weeks ago and notice that a bit of the label is missing from it.
Any help would be appreciated.