The engine has a rebuilders tag from Fresno, CA. On the distributor side of the engine there is a casting number B 52 848 8550. I can't find any reference to this number series on Stovebolt or on the GMC site. The original engine was a 228, but I don't know if the rebuild was a direct replacement or not.
Jeff,
After checking out the 228 block that I have in the garage, the casting number should be on the manifold side of the engine, just above the oil pan (for a GMC).
Mine reads 6107326, which means 228 cubic inches manufactured between 1939 and 1952 (according to Inliners).
After viewing your pics, that casting number appears to be on the head, and not the block.
I hope that helps
John
