This is for an old style weathershield assembly marked truth 45251. The spline OD is .323. Thanks, Roger
Lauren from SWISCO responded:
November 8, 2023
Hi Roger, thank you for posting,
Please review the 39-337 and 39-157 crank extensions that we offer. Both fit onto a 11/32" diameter spline. Take a look and let us know if you have any additional questions!