Ed, the answer to your question about it being as simple as a 235/216 swap is NO.

There was a post on this board about a month ago with regard to a 235/207 swap (1934..1936 chevy inline) that will likely be a lot more appropriate. If you have a 62 235, you will probably also want to get a later bellhousing / tranny so you can have synchro's for smoother shifting. Looks like a neat project!