I promised this to Firebird 86, but in reality, I'm giving this tip to everybody. It's a way to identify the oddball model numbers for the Chevrolet Trucks mainly from 1947-1959.

A)Half-Truck Cars:
1)1170:1958-1960 Sedan Delivery, 6 cylinder
2)1270:1958-1960 Sedan Delivery, V-8
3)1180:El Camino, 6 Cylinder
4)1280:El Camino, V-8
5)1508:1949-1957 Sedan Delivery
6)1514:1940-1946 Coupe Pickup.