You answer should be in the Tech Tips section. Also there is a cast date code for block and the head. The date code is a letter A B C etc (A being January), then a number (for day of the month) then final number for the year ie O (could be 1940, or 50 etc. Good luck.

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1946 1/2-Ton Chevy
1953 Chevy 3/4-ton Factory Stakebed