Abstract: In order to safely and conveniently assemble and service new design spring brake actuators having power springs located in the middle of the actuator, the actuator's rear chamber cover must be able to withstand high localized forces from tools such as power spring compression rods. A reinforcement and method for its installation is provided, in which a plurality of reinforcement plates is stacked on the rear chamber cover about a tool-insertion aperture, and the outermost plate is crimped about the aperture, thereby securing the plates to the rear chamber cover in a cost- and time-efficient manner. Preferably, the lip of the rear chamber cover aperture is stamped when the cover is formed such that the lip protrudes axially outward to help assure that the lip is captured between the crimped reinforcing plate on one side and the remaining reinforcing plates on the other side.