Trying something today. I ran a taper reamer into each hole from the top. A little draft on the holes should help with the release of the little divot.Yep. Gotta have a sharp edge there, the shear force from cutting actually pushes the sprue up out of the well, like primary extraction on a rifle.
I also drilled the hole for the set screw and retapped it 10-32. Those tiny little screws MP uses just don’t like to get tight on the pivot screw. That won’t be an issue any more.