Kevin: Those GMC numbers can be found (in a different format) near the front of the GMC Master Parts Books. Below is from the 1953 edition and shows only 100 series (1/2 ton). The rest are on the next page or two. The GMC plant codes are shown for 1953 and newer. P is Pontiac Michigan, C is Oakland California and S is St. Louis Missouri.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12 '52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
