Thread 'WI - 1973 Double Groove Harmonic Balancer' For Sale - WI - 1973 Double Groove Harmonic Balancer - https://forum.ih8mud.com/threads/wi-1973-double-groove-harmonic-balancer.1264898/It was threaded wasn't it
Not threaded but keyed. I have the nut and lockwasher as well.