Teeth were exactly the same on this one (this is a 12v starter), just inner spline pattern was different. I called Bill as well at Bill's Truck shop and he ok'd it. It fit on the shaft perfectly and no play. This is a Canadian rebuild from Wilson.
Maybe the older stuff was over built LOL - but then again it lasted 50 years.
I put it on last night and it works perfect - no more slipping. I kept the old one - core charge is $1, I'll keep it for that.
