Well, I tried again today, still no dice with turning it with the handcrank. I tried putting it in gear and rocking, but it won't even budge. Probably has to do with 23 year old flat tires it's sitting on.
I'm gonna pick up some Marvel Mystery oil, and put it in the cylinders next. Let it sit for a little while, and try again.
I did find the serial number on the engine while I was over there. I'll post the picture. If I'm looking at the website Dennis posted earlier correctly, then the engine is a 216ci, made I'm 1950? Maybe it was replaced at one point? Not sure yet.