A lot of info except what the body is made of.
Whatever it is it's not easy 'no see repair' without the profesionalism and equipment. I had corner damage repaired by a car body repairer and its un-noticable. Had I done it I'm sure it would have stuck out like a sore thumb.
Alternate: Fill hole with fibreglass and overlay with a vent to cover the repair.
Bob
June 2011