A driving light, or spot light, has to be above the centreline of the bumper. So, yes you can replace your fog lights with driving/spot lights, but only if you altered the positions of them
Wrong,
Not sure if you have ever seen a 205 GTi, Fiesta XR2i but these all had Spotlight / Driving lights on them. These all comply with the all important The Road Vehicles Lighting Regulations 1989 and had said lights placed next to the foglights.
Foglights are the only ones that have a height requirement which is no higher than 1200mm above the ground. there is no minimum height for spotlighs/drivinglights. The real thing is to make sure the operation wiring is correct. They can;t be on a sperate switch indpenden of the main beam etc and unlike fogs they don;t need a warning light, where as fogs do.