diassamble Wild M20 binocular tube

[brettpim]

I have a Wild M20 with a binocular tube that I am cleaning. There is a cloudiness inside the binocular tube head's left optics. I would like to open the head on the tube side. I have removed the four small black screws on the metal piece connected to the non-focusing eyepiece tube in these two pictures

And removed the two screws on the back of the moving mechanism for the focusing eyepiece pictured here

But that is all the screws I can see. Although the part that includes the non-focusing eyepiece is able to move a little bit, I have not succeeded in getting it off. Does anyone know how to continue the disassembly?

[brettpim]

Microscopy-UK has a quite detailed description of the disassembly of a Wild M20 binocular head. Thanks to viktor j nilsson for pointing me to it.