3769825...from what I can see.

Head reads B51 848 850. Is this a 235 head cuz it has an 848 in the number????

Thanks,
Tom

Nevermind, it is a 261. The number is 3769925.

But, what about the head???

Tecnically, the casting number for the head is on the drivers side near the valve cover.
The numbers you have are the date code, "B51" would be Feb. 5, 1961.

I believe it is an 848 from a 235, as all the ones I have seen have the 848 850 on the pass. side and "848" as part of the casting number on the drivers side...