I'm not sure if anyone has actually tried this yet as a solution to the 6309-836 bezel insert issue. So I figured I would post my experiment with it. These bezels seem impossible to find and there are no AM inserts being made that anyone knows of. The insert seems to be crimped in by the bezel edge, it doesn't look like it comes out. Big thanks to the fellas that colluded to create the bezel size guide on the forum. As you can see by the pictures the Seiko bezel insert is about 36mm with 35.5mm showing inside the rim. The AM bezel insert for the Rolex 5512 is 36.5mm. The other issue is the Rolex insert has an upward concave on the ID, presumably for a domed crystal. That was an easy fix to flatten it. I simply put it in my case back press with the flat disks and pressed it flat. You can see the picture of the Rolex bezel insert sitting on top of the Seiko bezel, it doesn't look like I'm going to lose much of the outer edge to file it down to fit inside of the Seiko bezel rim. So that's the experiment so far. The next step will be to file 1mm off the Rolex bezel insert to fit inside the Seiko bezel rim and file down the original top of the Seiko bezel insert as much as I can to try and get the Rolex insert to at least sit flush with the Seiko bezel rim. I'll post more as this experiment progresses.