Trying to open the rear (piston) end of a Geha (model 790, I think).
Saw Bo-bo's suggestion if using a paper clip in the hole below the piston threads, and am unable to figure out how to use the paper clip to open it.
The paper clip only goes in a couple of mm. I've bent the ends of a couple of paper clips and can't figure it out.
Thank you in advance.
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