FYI: When I was installing KH wheels on new mechanical brake drums, the rear wheels did not fit over the emergency brake part of the drums. The spoke
heads had to be filled. They fit the old drums.
Good Luck
Dan
Appreciate you sharing your experience. To clarify though, for anyone who finds themselves in the same boat, I think you meant to say that the spoke ends had to be "filed" not "filled." They won't clear the rear drum otherwise.