Dave, This engine being a 1957 do you mean push rods are independent from 1950-55 and 1956-62? Does a 1957 have hydraulic lifters?
Push rods from 1950-55 with hydraulic lifters and 1956-62 with solids or hydraulic lifters are all the same. (About 11 1/4" long).
A 1957 engine could have either solids or hydraulic lifters depending on that it came out of and what has been changed over the years.
