Installing this drum took a time or two, as I had to rotate it with my fingers, until everything lined up and all fell into place.
More full disclosure: I resused the pump gasket. I have heard arguments from both sides, and I know the correct thing to do is replace the gasket. However, I did not feel confident I could get all the razor blade shavings out of the transmission casing when done. So, I left the gasket intact. Time will tell if I am a fool for doing this or not.