Block casting code is on the front lower part of the block, above the oil pan: 3733950
Head casting number 3836850 GM-4 and B55 848 850.
Behind the starter A123, no captians bars rather a raised circle.
The distributor pad is blank - you can see factory fly-cutter marks and no stampings.
There is paint evident behind the starter - a medium/light blue metallic. Kind of resembles old industrial blue,green hammertone paint.
If I had to guess, I'd say this was a very early block (53?) used for a 261? it has the smaller oil filer lines, not full flow.
Last edited by distributorguy; 09/16/2015 9:02 PM.
