A SM 420 will bolt to the bellhousing found on a 216 TRUCK engine from 1948-53. The bellhousing behind a 216 in a passenger car has a totally different bolt pattern for the transmission, and a different diameter hole for the bearing retainer IMHO. The SM420 can be had in either open driveline of torque tube configuration at the rear. The basic transmissions, other than the rear bearing retainer, are the same.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
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