I have a 2002 ML with the OEM bull bar. Same problem. Did you ever come up with a solution? I was thinking of using a piece of 1" x 1" Stainless Steel or Polished Aluminum (1/8" thick) by 8" long on each side and mount it to the back of the bar with 2 screw/bolts. I could then drill a hole wherever I needed for the mounting bolt from the light. No extra holes in the bar was my goal. If you have a photo that would be appreciated.