Hella FF worklamp on swivel sheetmetal mount. Dual 55 watt bulbs, you can choose your beam pattern, and it swivels and pivots up and down for the ultimate illumination of your choice. Mine's going on 9 years and 100k miles with nary a hitch. Be advised that some local regs require it to either be covered while driving, or only light in reverse. Go to Hella's US website to see it.
Not sure how strong the wing is, but sounds like you may have to be careful. I mount a removable 55W waterproof halogen work light on a bracket attached to my rear roof rack. When I need it, I pop it on and plug it in to a power line running to the rear (about 1 min).