Ever wonder why GM pickup rear bumpers have been an option for so many years?
The reason relates to trucks being mostly for work. Though protecting the bed from minor rear damage, a bumper also kept the driver from backing up against a loading dock. GM found that many farmers and construction workers had been removing the rear bumper to get the truck flush against a dock. This eliminated most of the gap between the truck and dock. Broken legs of livestock and employees during loading were also greatly reduced.
The following picture is an example of a 1955 and newer GM step bed pickup. Its owner went against the current trend of adding the optional rear bumper during its restoration and kept his truck basic. It is important to note, that to protect the license plate bracket without a bumper, GM placed it on the left side. Holes are in the middle of the rear cross sill from the factory to make it easier for the dealer to install the rear center license plate bracket while adding the optional bumper.
Note the rear spare tire arm is at an angle to also protect it from damage if backing or being even lightly bumped in traffic.
This picture shows an optional right taillight. From the assembly line this truck would have only the left light with attached license bracket.
Without optional bumper. Owner has added a right tail light. (above)
Factory installed optional bumper including correct tail lights and license bracket (above)