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353 22 C 1404

353 = 350 series (2 ton) 157" wheelbase (the 3 at the end of 353)
22 = 228 engine
C = Oakland, CA assembly plant
1404 = production sequence number (starting with 1001) = 404th truck of that series off the line

I am not good at decoding GMC codes, someone will correct the above information, if any of it is wrong.

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