3731548 1957 283 block, date code L-3-6 (December 3,1956). Stamp clearly visible on front pad reads F0124S, decodes to a Flint Michigan block, stamped on December 4, 1956 and installed in a Vette or car with a Powerglide and 2 barrel carb. The block was bored to .060 and then sat for a few years before I purchased it. Seven of the cylinders look good and with a honing are ready to run. Cylinder number one has some pitting as shown in the last picture. Cylinder one could be sleeved and bored .060 to match the others, or the whole block be bored again. Other than that the block is in great shape. The main caps fit tight in the saddles. I also have a period correct freshly ground .010/.010 283 crank casting number 3876764 ($200.00), available separately if interested.