I removed the rear bull bar from my SIII and pondered on the holes left in the overiders. I decided to use chrome screw covers and riveted them in place. I think they look quite acceptable until I eventually replace the over riders in the distant future (other places to spend the money first)
Looks a lot better than bull bars or holes.
When you decide to have the overriders re-chromed, it will be a doddle to close the holes with a MIG welder, grind, sand and polish and then send off to the chromer.
I had the same problem on my rear bumper. I simply filled the holes using common domed chrome bumper bolts from my srap box. No one ever noticed or comented on them, even the judges.