Crankshaft

The only difference on the 273 crank....auto vs. manual.....is the manual crank went through a final machining process to finish the end of the crank for a pilot bushing. The hole for the converter button is the same for both. Now if you're swapping a '64-7 crank into a '68 and newer automatic, you'll run into diameter problems but that has to do with year, not manual vs. auto.