If no one else posts information, see if this 1937 information is helpful.

Your engine will be different from the 1937 216 engine (but your engine is still a stovebolt six, probably a 181 or a 207, or maybe even a 194). Some casting numbers are shown on this web page.

Here is other information that might help:
http://chevy.oldcarmanualproject.com/models/series1.htm