This is a 39 stude champion engine, sure looks like the mystery motor...a lot more than a mopar engine does.
I don't a lot about these various flathead engines but check out post #70 on this page for oil filler location - http://www.jalopyjournal.com/forum/showthread.php?t=429644&showall=1 Post #72 says it is a Nash. Perhaps a lead?
I always get a kick out of the threads where people doubt Squirrel. I LOVE the vintage speed parts on this. Wish I could find similar things for my Hudson!
Flathead Nashes had the intake manifold built in to the head, at least the two that I ever worked on did.
Please do argue with me, because I do make mistakes, and I want to know when I'm wrong. But have a little bit of do***entation to support your argument, maybe?
I agree it looks to be Studebaker. The engine number is on that little boss at the top rear left side of the block by the oil filler. The number would nail down the year of the engine. I guess it is the little Champion engine and not the bigger Commander??
The Champion engine number does not start with a letter, the first engine number in 1939 = 101, 40 = 34101, 41 = 101201 42 = 186301 46 = 216501 etc