There will be a casting date on the right side of the block, next to where the starter sits. About the only thing I tell yo for sure about the code from by the distributor is that thengine came from the Flint plant, there should be another letter in the code. I take it that the casting number you posted is from the cylinder head? It's probably actually 3836848, they can be hard to read, especially if the engine is grimy from years of use. That head comes up as a '56 or later, so that points to at least a 235 full pressure.
