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 .