A quick update... several people have asked about the Hario grinder modifications, and I'm sorry to say that Max's attempts to modify the Hario with bushings did not succeed. The tolerances on the Hario are just not tight enough to allow a bushing to consistently work. I'm not sure if the issue was that each grinder is different from every other, or if most of them simply wouldn't work even with the perfect bushing.
I hear that the search for a more suitable hand grinder is on, and there is a candidate, but I don't know more about it right now.
That isn't to say that the Hario is a bad grinder, but it isn't going to be very consistent, especially at coarser grind settings.