You will also need to get the stamped engine numbers off of the block, between the starter and the distributor, to see which engine you have now. There's a chance it already has the 235 upgrade. 216's just didn't last very long if you used the truck as a truck. I've got an old 48 with only 18,000 miles on it and it has a 1955 235 in it.
Good luck getting and fixing up and old truck and welcome aboard,
Scott
