Hi Tim:
I think way back you, PeeWee and I were involved in this discussion. The page link to the Woodie Club with the measurements is now gone missing. There may be more info in this discussion that I haven't clicked on yet.
https://www.stovebolt.com/ubbthreads/ubbthreads.php/topics/409598/tclederman.htmA friend of mine in the tool and die business made me a tool with needles which will conform to the width and depth of the grooves. I will look for it over the weekend.
Regards, Mark