The Stovebolt Site Forums The Parking Lot Panels 'N Burbs GM Panel Truck Assembly line Photo, Norwood, Ohio Plant

If I'm reading this right.
Looks like the rear body sills were different for a specific year,
tonnage and whether the truck was ordered with Clam Shell doors or Barn doors.

Master Parts Catalog 1929-1954
Group Number 17.166 PANEL, Body Lower Rear, pages 776 and 777

Wonder what the differences were?
Asterisk note: When used on Sub. w/end gate hinge cutouts have to be made, cross sill reinforcement must also be retained.
What ever that means.