There really isn't that much material there once you cut the shaft and bore the hole. Once you chuck the crank and indicate it in you should have a pretty rigid setup. I would chuck the hub end and cut off the clutch side. Plenty to grip to there on the hub end. Center drill the crank and go. Your hole will be rather shallow as I can see it. I looked at a crank I had here for reference. Before I did any of this I would rework the hub end to rid the crank of the LH threads. Don't know of any crank pictures out there yet. I think Huey-pilot will be closer than anyone. Wouldn't it be great if we all lived close by and could see things first hand? Here is a picture of two cranks I sent to Av8tor a while back. Maybe these being next to each other will help. Visuals always do for me. I think both you and foamcut can do it, just dig in.