A system is provided for mounting a lamp having a plurality of different types of mounting members. One of the mounting members is a rigid tray mountable by fasteners flush upon a surface of a vehicle to enable an on-surface mounting mode, and other of said mounting members, such as a grommet or bracket, are mountable at least partially in an opening or hole when present along such surface of a vehicle to enable an inset mounting mode. The different mounting members each engage a common shape housing of the lamp, such as round or oval, so that by selection of one of the mounting members, on-surface or inset mounting of the lamp can readily be achieved. One or more common engagement features are provided along the housing to facilitate engagement of the housing of the lamp by mounting members in on-surface and inset mounting modes.