I got most of my info from old Motor Truck Repair Manuals (Lots of them on ebay) and my GMC 633 Shop and Parts Books plus years of collecting and reading about military trucks.
Is the civilian-vehicle purchasing a common occurance?----Yes
Is that why inliners said military 302 is side-mount while mine is front-mount?----I don't know for sure, but reread my second paragraph. This is my best guess. If it has a Holley two barrel, horizontal, rear intake carb it is most likely the military engine.
Can I use the army serial # and vin # to find out what its specific duty was?...Is there an army archive for such research?---- Maybe, I doubt it. These were general purpose trucks used to haul general cargo around bases. I don't know anything about Army Archives. You can search the internet and probably find out.
