The frame numbers, stamped on the top of the driver side frame rail, adjacent to the alternator, are the last 8 digits of the 12 digit VIN. Check these numbers against the numbers on the VIN tag, found on the driver side door jamb. The VIN can also be on the "A" pillar or "B" pillar.
The last eight digits, breakdown like this, on the '60-'64 Chevy trucks:
1st digit on frame rail is Truck type - 4 = Pickup
2nd digit = Assembly plant
3rd-8th digits = Vehicle number, beginning with 100,001
The last eight digits, breakdown like this, on the '65-'66 Chevy trucks:
1st digit on frame rail = Model year
2nd digit = Assembly plant
3rd-8th digits = Vehicle number, beginning with 100,001
Last edited by 4-5-6 Chevy Trucks; 05/07/2011 1:09 PM.