Put a mark on the two fingers you insert into the ball, half way between the two knuckles.
Now put just the thumb into the ball, and lay your fingers across, but not in the finger holes.
The closest edge (not including bevel) of each finger hole should be in line with where you put the mark on each finger.
If you have inserts, use the edge of the hole in the insert, not the actual hole drilled into the ball.
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