Alaric is right that we have to be really careful not to self-assure ourselves that a nonstandard lighting configuration is a good idea. But I don't think that necessarily means "don't add any lights at all". Use good judgment, make sure to respect applicable local regulations and general color and placement conventions (red to the rear, white/yellow/amber to the front, amber to the side) and don't operate the lamps in an unusual or potentially confusing way (no flash/strobe/"pulse" operation of lamps that are supposed to be steady-burning, for example), and that still leaves a pretty large canvas to paint on, in terms of what lights to install. Bigger/brighter lights positioned to accurately show the height and width of the equipment, are probably a good idea if the equipment is operated on roads with much traffic and/or short lines of sight to intersections.