Slant six flywheel for manual trans
They're fairly rare here in the U.S. Only came on a few cars in '63 with that Autolite direct drive starter. I parted out hundreds in my 32 years as a Mopar wrecking yard owner, and saw only 2 in a 1963 model, and just a few in 1962. '60-1 all had them IIRC.