I'm pretty sure the tapped holes in the hub are coarse threads (3/8"-16). Those who drill/tap the crank usually use a SBC bolt which is 1/2"-20 (fine thread) however I believe it's unnecessary unless the hub I.D. is worn enough that it want's to fall off. Warming it on a stove for a bit makes installation much easier.




1952 1300 Canadian 1/2 ton restomod
You Tube