Vent Cleaning 2011 R-Vision - Trail-Lite Crossover Floorplan: TLX210QB

[New Camper]

I recently purchased a used 2011 R-Vision - Trail-Lite Crossover Floorplan: TLX210QB. I'm cleaning it and trying to get all the bugs and debris out of the bathroom vent and the cabin vent but can't seem to get the screen out to access. I tried removing the housing and the vent handle in the bathroom along with the nut holing the switch in place. But the unit that has the screen on it seems to be a large part that won't move. Am I doing this wrong? Do I need to clean them from the roof? A little worried it wouldn't provide much support. This is my first camper so I'm a beginner at all of this. Hoping someone may know how this is done. Also looking for a manual for the trailer but don't seem to have any luck finding it online. Any help would be much appreciated.
Note: I'm also looking for a replacement kitchen double sink but not much luck there either. Thanks in advance from the "New Camper"