Just my opinion, I like it, a tasteful street rod type touch that would give the car a more expensive look, and there is no reason you could'nt make it look as though the factory did it, in fact if the factory would have, someone installing square headlights would be getting a bad rap. All the old cars from the beginning till mid 70's ( at least American cars) used round headlights, and had variouse headlight bezel designs to compliment the cars style. I am not saying the square headlights are bad, they look fine on most of the cars they came on, Regal and other G bodies, the round just look better (my opinion) . They are on all old muscle cars, square or round body styles, most exotics and most Lemans race cars, and from a natural aspect, light emits radially (except lasers) in all directions, not a square beam, ok, I am getting carried away, I still think it would look good as long as they have a factory installed finish. A good thing to do would be to buy a spare Regal header panel and use it for the mod or at least keep it in the attic in case you sell the car ( I would store the original), that way no value lost, and the new owner could choose. Again, make it look like the factory could have, do'nt put on some kind of plastic covers or such. Good luck.