Underneath the glove box is a plastic air vent tube with big holes in, this is where the air comes out.
This is secured by 2 big plastic lock type fasteners that need a half turn to release.
When off you will see the 2 remaining glove-box screws, remove these then it will come away but be careful to unclip the light cable.
The pollen filter cover has a couple of screws, one on the bottom, one slightly higher, once out the cover pulls away from the bottom to allow you to lift it slightly as it is clipped onto the top of the housing.
Look at how the old filter is sitting in there before pulling out (so you know the orientation)
There is enough room to slide your hand in to check for rubbish etc and on mine i hoovered this area before installing the new fellow.