I sold a Snapper tiller a few years ago that is the same as the IH one. Are you looking for the rear half that attaches to the tiller? If so, I can get some picks and measurements today for you.
Here is the Snapper shaft. It was sold with the tiller.
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This is my tiller I still have and can get you the measurements you need. It is a Cub Cadet model #193-356-100 if you need to do any parts look up info.
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