The Stovebolt Site Forums The Shop Area Engine Shop need help identiying 6 cyl - 235 or 261 or 292 or ??

I have a inline 6 cylinder in a 1962 C10.
The casting number is 3836848.
And another number code F0123J.

I am trying to decode this so I know if this is a 235/261/292 (or even a later 230 or 250). I assume it is a 235, but not for sure.

Can anyone help me?

I went over to the INLINERS website, but was unable to find any match - if it was there I missed it.