A closer view, similar to shot 1, clearly showing the return holes in the inner tube. A question to ponder: Why do the Cass stacks have six-hole rings? Lima repair parts books show both Lima diamonds, and Radley and Hunter stacks as having eight bolt holes in the rings. Why and when the change? WVP&P, or MOWER LBR modification? Patent dodging?

Note that all internal rivets are flat.

Photo by Rick Brigger