Would bet there is a rectangular, removable, and
sliding drive-pin somewhere in your stash.
Some manufacturer went to a lot of trouble designing
a crank that could fit a number of rings nicely.
And in different tooth-counts, also.
The worst company for making rings and cranks with
drive-pins of cranks matching the distance from the
ring axel-center to where the drive-pin hole is supposed
to be ... Miami ... and the worst of the Miami ... F-M