To the best of my knowledge the first big block a bodies were the 67 383 darts and barracudas......your trans, if earlier than 67 would be from a 6 cyl or 273.
I'm not too familiar with a bodies mostly just b and e bodies. But here are the numbers. Selling the trans if anyone is interested
C-95658-L
C 95639U
Will ship but buyer pays shipping.
