The full rear quarter panels for the 1947-55 Chevy/GMC Suburban were made all the same at the metal stamping manufacturer. To save money these panels were not made different if the Suburban was to have the double doors or the tailgate style opening in the rear.
Thus, when the Suburban was provided with a lift and tailgate combination the 4 holes for the “double barn door” hinges in the quarter panels were filled with rectangular rubber plugs. This was not just for appearance but prevent rain water from reaching the body interior.
These photos show the plugs painted in body color; however it is questioned if this is correct. By 1950, Suburban buyers had the choice of the 12 pickup colors. It would have been more economical for all to have black rubber plugs instead of 12 boxes with the optional color prepainted plugs on the assembly line.
The other thought: These plugs were painted when the full body was given its final color. This would mean GM planned on the enamel body paint being of the quality that would successfully adhere to rubber over the years. We don’t usually see this combination in other GM vehicles. Special paint for rubber only is used!
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