We had one that was worse than that and it was in the third bay in from the wing tip so we could not reach it well enough to work it from the tip as are arms were just not long enough. We made a hard wood block from a pice of oak salvaged from a wood truck pallet. We were able to get a very good fit by using the first bay inside of the wing tip to fit it to the exact shape of the leading edge. When this tool was finished to a vert smooth sanded finish it was used like a bucking bar to push out the dent from the back and to be a form to use to smoth the leading edge aginst. It was necesarry to cut a four inch hole in the lower skin about 12 inches behind the leading edge to get acess. The leading edge was returned to the correct shape and smothness with good and careful tin work, it was so smoth that no bondo or that kind of filler was needed, the area was sanded back to primer and hit with a coat of the original high fill primer and sanded to the desired smothness for painting, then the paint was repaired per the original paint build up. The whole cut was flush patched with a flush rivited doubler and cherry flush rivited patch which was then lightly filled with Super Fill and the area preped and repainted like the leading edge.
The aircraft won best workmanship at Sun-N-fun after the repair and if you were not told you would not find the repair. It only took us 20 hours to do all the work up to paint prep to do the repair and return the aircraft to flight, the paint took a long evening as it takes about ten layers to follow the original coating system and there was a lot of tapeing to repair the difrent colors and pin stripes.
You are in luck as you can work through the landing light hole and from the wing tip end (with the wing tip removed). With good work you may only need to buff out the paint when finished the tin work, good luck.
Best regards,
Vern