Step 7: Low mag variation
Carefully cut the plastic mounting so it is not much longer than the thickness of the objective lens.
Move the rubber casing of the intact monocular back from the front.
insert the spare objective lens in front of the objective, and put the rubber back like it was. That's it!
The magnification will now be about 10 X, the working distance about 200 mm (8 inches).
The microscope mount might be too small now, but hey, you can use the enlarger stand!