Motor City Flathead question

[Moonshin'R]

Ok, I looked over the upper block and found the date code H/24/M (7/24/1950). I see what you are saying about the heads and the 325# on it. It looks like they are unmarked OFFY heads. I will continue to look around the block as I am cleaning things up to see if I see any numbers or letters. Does anyone know what the "F" and incomplete circle might be? listed in the pictures provided in earlier conversation. Thanks for your help so far 19fordy.