We fabricate "baseplates" out of Pre Primed 1 X stock or 1 X composite stock, or even 5/4 stock. Dependant on whether the electrican is required by the town/state to do the actual removal/re-install of the utility box, or not...we always do the baseplate work. We do this for all the areas that require some kind of additional "fitment" of an exterior fixture where lap siding won't align properly with the fixture(s) - (properly weather-sealed).
Sometimes, we may have to fabricate the baseplate, then cut it in half, then install the two halves from opposite directions - if it is not possible to easily have the fixture disconnected.
Examples:
Linear Mode
