DC08 dismantling of cyclone section?

I have used my DC08 for cleaning concrete dust, and the cyclone section is fully blocked. I have tryed to clean with water and also with compressed air, but can't seem to get all out. I therefore try to dissassemble the cyclone section. I have taken off the handle and removed the 3 screws from underneath, but the cover is stuck at two points, and I can't see any screws, and don't want to break anything.
Has anyone successfully been able to dissassamble this part?
Any help is much appreciated

Best regards