Hi all, I've had a Mamiya C22 for about 4 years now, but unfortunately I've never been able to use it. It was working fine, checked at a camera store and everything, but as I was loading my first roll of film, the film advance knob jammed. I asked my local camera store what the expected repair cost would be, and their best guess was "at least $200". Now, that is way outside of my budget as far as a repair goes, especially when I could buy a new C22 body for about the same price if not less, so I put it out of my mind for a while. Now though, a few years later, I've really got an urge to shoot square format. I figured, why not try to repair it myself? After all, I got the camera for free from a family friend, if I'm going to try a repair on any camera, it's gonna be this one. I tried to find any kind of guide, but it seems the C22 is not a popular model. To get into the body, I followed a guide for a Mamiya C33, but the screws were in slightly different places, as expected. Still, I was able to gently peel back the siding and remove the screws painlessly. However, I've encountered a big problem: I can't remove the metal side plate because I can't figure out how to remove the advance knob itself. Here's some photos of the progress I've made and the knob that's impeding my progress. There's a hole in the knob under the rubber/leatherette, but there doesn't seem to be a screw inside. Can't tell how it's attached: Any advice would be appreciated, even if it's just general repair/cleaning advice!