Thanks for the welcome guys. Truck is going thru a frame-off, not much for taking photos but will try as I get time. I'll post on General Truck to see what reponses I get. 1957 was the first year GM offered the 283. The numbers I have came from GM Canada and its an estimatation as there are no records of options on the trucks. I believe there were 2671 9313's built in 57( I have to find my letter) of which GM figures well over half were 6's, and of the remaining trucks you have a mix of long and short boxes and the 265 V8. One of the reasons to see if any others survived is maybe the owners have some better info. Only the Canadian GM used the Chevy small block.
Gord