It is a little out of round, but not enough to fix the problem. Between 1/64" and 1/128 "out of round. As I mentioned, a 1/32" increase in diameter would have made it big enough to just slide over, but just barely.
I wonder what the diameter of the cups were originally. That would have been fun to know. Guess I have to put this on the list to find when I go to the junk yard.
