Truck VIN - 55 or 56???

[bufordtjustice]

Hi Guys

My name is Mike Barr and I live in Northern Ireland. I was hoping some of you might be able to help me. I just bought a 1955 chevy stepside (or so I thought) but having difficulty in decoding the VIN. On the frame rail under the cab it reads 562003138

Does this mean its a 56? What does the 2 stand for after the 56? Is it series 2?

Is there anyway I can trace the rest of the numbers / letters? It now has a 79 Camaro front end so no vin at steering box or door jams.

Any help would be much appreciated.
Cheers
Mike