Originally Posted by Sccrbrg
KC makes a factory fog replacement. But fog lights and driving lights are not the same thing.
You can buy the KC Apollo Pro series in fog, driving or long range(aka spot). This light is 55W, which is a direct replacement of the 6inch OEM light.
KC HiLiTES 452 - KC HiLites 5" Apollo Pro Series 55 Watt Fog Lamp System with Stone Guards in Black - Quadratec
"KC Apollo lights feature an extremely tuff black Polymax round housing with a sleek, flat profile. Their optical quality glass lens, halogen bulb and polished reflectors combine to generate a super bright, specially focused beam of light. The two axis mount provides for easy aiming. Apollo Series lights are available in 6" round or 5" round models, and come in a choice of Long Range, Driving or Fog light patterns. And like all KC lights, they're backed by KC's exclusive 23 Year Warranty.
This is not the only solution, but a commonly suggested one because it meets the OP's conditions (rock guard, etc..)