Reproduction transmission cover (picture). Notice the clearance for the shifter.
A 1950 216 and bell housing was originally bolted on the crossmember of your truck. A 1957 235 will fit a/the 1950 bell housing. A 1957 SM420 and 1950 SM420 are the same, except closed and open drive shaft connections and a few minor things. If your 1950 was originally a 3 speed column shift transmission then you have to change the transmission cover when going to the 4 speed.
You need the 235 engine to be in the same position as the 216. Fan to radiator. Engine front mount. Carburetor fuel bowl float position.
If you modify the original crossmember you pass the point of no return in my opinion.
"Adding CFM to a truck will only help at engine speeds you don't want to use." "I found there was nothing to gain beyond 400 CFM."
