bjr
Veteran Member
I just got done puttin' the correct width pulley on a Delco 10si. It was a machined pulley versus the automotive stamp steel pulley and the machined one had a counter bore that wouldn't let the original nut go on and it takes a special long neck nut (to go into the counter bore. 11/16" dia. shaft. Just get the right nut if you go with the wider pulley for the 5/8" belt. I got the nut from the local Alternator rebuild store. bjr