A method for rapidly generating the gray-level versus brightness curve of a display includes the step of obtaining a portion of the gray-level values and their corresponding brightness values. Various implementations of the present invention may be utilized to programmatically vary the voltage and or frequency utilized by one or more components within a processing system to effect changes in system and or component margining. The method further includes generating a memory map definition of the memory map using the at least one identifier and the associated at least one value. A rear seal is also provided to seal the rear of the electronic display module to the electronic sign mounting panel. A gap exists between the first supporting portion and the locating slot.