Id get the michealometer out .
The Irvine 40 ring in the K&B , you have to hold your mouth right ; Dosnt seem to fit , but it does . Revolves Free once fitted .
Im Figureing the TWO S T Part Numbers are for TWO Ring Specs .Earlyer for Chome Bore ( maybe harder ? )
LATER for the softer Un Chromed Bore . ! ??
Actually Chromed Rings ( or is it chrome molly rings ) in old iron Norton Bores , are a relevent concept , perhaps .
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The DEBURRING Trip , removing all sharp edges - cept maybe the top outer on ring - would ease the fitting .
DOES IT ENTER EDGEWAYS FROM ADJACENT , I.E. will the outer edge locate in the outer edge of the land . Sorta figure * like . ! ? ?
Fit in a used pistons likely superior . Take up the slack .