White cab over truck ID needed

[Guest]

We recently purchased a White city tractor that was probably made in the 1960's. It appears to be a model 1500. It has the White Mustang gas engine and is a single screw. We know it was built before 1966 as there is a rebuild plate on the engine where the original moder number plate should be. The truck has a 5 speed transmission. The front of the truck is flat with a bumper-grill combination. Can anyone tell me where to find the serial number or other information on the truck? I have a 1961 Motor's truck repair manuel so I have that information.