1956 is before my time in procurement with the DOD. However, with the exception of those purchased by GSA, most vehicles were obtained through contracts directly with the manufacturer through TACOM in Warren MI. Standard vehicles were generally obtained for agencies and were basic stripped down models. The ones I have seen of that era were 1/2 ton, short bed, small window, 6 cylinder, 3 speed, electric wipers, no radio, some had heaters, no extras. In your case you have what most people find on a vehicle that has been driven, modified, and repaired to whatever standard the last owner needed to keep it on the road. Not uncommon for a 60+ truck. Since it has a V-8, leave it in, fix whatever needs to be fixed to make it your vehicle and drive it. My friend recently picked up a 57 that was a former AF truck. It did have the data plate and was the standard model as described above.
Fred
