Identifying Truck Frame

My '51 Chevrolet has a different frame than that year model. Is there any way to identify which frame it is?

I doubt that in 1951 GM bothered to stamp the VIN then called the serial number in the frame…There MAY be some ID markings, but it will take a Chevy truck expert to figure it out…

There would be different '51 frames for the different capacity trucks, maybe yours is a heavy-duty version.