What do these letters on the block mean?

Hi All: I hope you're enjoying driving your slant six powered rides as I am. I noticed the letters "BH" molded into the left side of my 1974 Windsor built replacement block, and the letters "AAWJ" molded in the right side on my 1974 Duster. Does anyone out there know what these letters mean? Slant Six Dan, any ideas? Thanks, all. cruiser

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Author: Cruiser