JimGMC, to try and keep things straight, lets only talk about MDReed's (OP) truck in this thread. If Ozark45 has a question he needs to start a new thread...it gets confusing when two different questions are answered in the same post.
MDReed More info on your truck.
Chassis serial number 200S10 1314 breaks down as follows...
20 = Van Nuys Assembly Plant
OS = 1946 first series 1-1/2 ton with 160" wheelbase
10 = Month (October)
1314 = Unit number starting with 1001
From Mike B
Your truck was built at the Van Nuys plant in October of 1948
The Van Nuys Assembly Plant open on December 1, 1947
So you have a “42” model built in 48.
As for the cowl tag, the only references I found to "MASTER" being a truck model is in the 1938 and 1939 data book. But below is a 1942 1-1/5 ton with 160” WB pre-war tag with MASTER printed on it. 9MS42 x237x hard to read. The 42 in the month position could be the week number of the model production year. All civilian production of cars and trucks ended in June 1942.
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Per the GM Heritage Center the Van Nuys plant is listed in the 1946 Truck Specifications. Can you share where you found that it opened on Dec 1, 1947. I find it hard to believe Van Nuys made a Model "OS" (1946 first series 1-1/2 ton truck) in 1948 after the AD's had been introduced...
Mike B
