Partially correct.

Is your truck going to be 6 volts or 12? That makes a difference for the flywheel. The 302 has a 6 bolt flange. Only 1955 and possibly 1954 248 flywheels are 6 bolt 6 volt. The later 1956-1959 270 flywheels are 6 bolt 12 volts.

Look up James Larowe. I'm sure he has the flywheel you need.