Chrysler put them on three different vehicles on 64 and up. 66-69 Hemi, Canadian built /6 64-66? and 68-71 truck with 361 & granny trans. Hemi has a 9 tooth bendix truck and /6 has 10. I think the Hemi one has more windings too. Not sure if 61 and back will work either, dads 400s in his boat had direct drive starters too.