+1 to vccomm here. It's due to a change of ring design. The late PowerTorque bottom ring doesn't use an expander; not sure when this came in though.
BTW, did you check the bore size? 2.420"/61.47mm is standard bore.
It was more common to rebore the full crank barrels back in the day, than it is now; oversizes go up in .020"/0.50mm increments.
Cheers,
Gadge
"ODK Mods can explain it to you, but they can't understand it for you..."
"Crazy can be medicated, ignorance can be educated - but there is no cure for stupid..."
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