Can’t figure it out at all.
Well, it all depends on the vintage. The axle is a hex head screw with a nut on the other end. On early versions like I have the response adjusting knobs were held on with 2 small screws. You just remove the screws and the axle can be unscrewed. Looking at the picture of the new ones on the YYE store it looks like the knobs are not screwed on. I don’t know how they come off, if at all. So maybe you can’t.
Edit: OK looking at the pix here closer, it does appear that there are 3 small screws holding the knobs on. Get something to remove those and you are probably in business. At least they look like they are held on by screws in the larger pix.
Screws are there under the stickers.
Ahhh, ok. And now when I look at mine I see that it too has the 3 smaller holes around the edge of the knob that mistook for screw holes. They’re not.