Now it is time to address that dang bearing spacer.
Master Machinist Sandwich knows that the slop in the rear upright was about 0.004 inches. He just knows from experience. So he goes off to the lathe and whips out a spacer out of Godzilla, pre-heat treated 4340. This takes some time. Notice he makes the entire shim in one operation and then cuts it off. You have to be SURE your ends are absolutely parallel.
