74 to 64. ???
The snout on the Torque Converter is larger on the '74 and wont fit the '64 crankshaft.
The '74 has a linkage type shifter, the '64 is a cable type.
The '74 has a slip yoke type tail shaft. The '64 is a bolt on flange type.
The '74 engine and trans will fit along with the driveshaft. You would need a linkage type shifter.