Except that in 1960 (and 61) a big block Mopar would have been the old extended crank version, and the only available automatic would have been the old cast iron Torqueflite. Three speed manual, too, but . . . .
Anyway, I know that in 1962 the Dragmaster team built an A/FX max wedge 62 Dodge Lancer with the new style (modern) big block. I'm not aware of anyone putting a big block Mopar in a first generation Valiant or Lancer before then. But I also doubt that very many SBC's were ever swapped into the earlier Valiants or Lancers, either, or that Hurst ever sold many kits to do so.
Hey - I'm up at 4 am. My dog had to go out, so I figured I would check in here while I was up. . . .