Well I finally found the casting numbers (thanks to the info on this site!) and now it looks like I have a 1954 first series 235 in my recent 1949 3100 truck. The block is marked casting 3835911 by the fuel pump with F54Z stamped next to the distributor, and the head is casting 3835913. I guess the swap was sone a while ago. Is this better than having the original 216?

Anyway, with the plugs out it spins by hand (a good sign) and I want to put some new motor oil in it before spinning it with the starter.

What's the oil capacity for this engine?

Also - the generator? has a "12 volt" marking on it. Is this system positive ground or negative ground?

Thanks!