Elgin ID again...

[antiquecycles]

Could be 'MOS-I', which would be 1944. -Adam

Bite your tongue, Adam!
Actually, I took a long, close look. It is MOS 770396.

A friend of mine (self proclaimed Elgin official) said it is a '37. He confirmed what Scott (The Black Monark) said; it was most-likely a base model with no tank or truss rods. It came with surplus forks that were Westfield. This can be 100% correct or a bunch of malarky, no way of knowing.
I have since found 4 photos of similar models with the same fork set up.
Now to find that tank...

Kris

 

[The Black Monark]

Can't find the date code chart for Musselman right now, but IIRC A=1936, B=37 C=38...F=41
The symbol indicates the yearly quarter of production, triangle, circle, square, diamond...? Don't remember.
Rear wheel might have come from the bike that donated the fork.