Was there a specific casting mold number used on '67 A6 Camaro compressors (rear backing plate)? Different casting molds for different GM models? I have a 6555302 casting dated (H 16 6) (August) and a 6556406 casting dated (K 27 6) (November). My build is 11B. I know the 406 casting is beyond my build date, but here are two compressors within a couple months of each other, with different casting back plate numbers. Also as a note, the front castings only have casting dates. The AIM calls for a model number 6550133 (which was just a sticker on an A6).
There is ample documentation of engine block and head casting numbers, but I'm searching for correctness in compressors. Also, were the 1966 compressor castings used for early 1967 model vehicles, just as the 1966 engine castings were used for the early '67 models?
