How to remove advance lever on Olympus OM4

Hello! I am trying to remove the advance lever from an Olympus OM4.
Whatever I've tried, I cannot seem to remove the top cap/screw from the lever.

I've read that there may be two versions, one where the top screws off, and one where it is glued on.
Does anyone have any experience with this? Thanks!

https://learncamerarepair.com/downloads/pdf/olympus-OM-4-service.pdf
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