Bubblemaker,
It is a good practice to post the make, year, and model of your truck. Often people post questions regarding the truck in their "signature", but often people post about another truck.
1951 Chevrolet 3100 pickup
Here is a lot of information about your truck. The information on page 53 of the a...ntains other identification information. Here are locations of engine codes. These codes will tell you about the date/type of head/block you have. Post the codes you find and people will help you decode.
There were no standard GM markings/codes/plates on the truck to indicate for colors/options/accessories for trucks during the Advance-Design years (1947-1955st trucks). As mentioned above, some people have found under-hood (under-bonnet) cryptic crayon/chalk markings that might have been put there by worker(s) on the assembly line.
