Thanks for posting the pic, definitely something unique. Would be nice to have more examples. Looks like a large pointed punch was used, much different than what most folks would describe as a punched hole... like maybe seen using conduit hole makers.
Most of the original holes for accessories I have seen were done with a hole saw and can leave an edge on the back-side like expected on some cars, like GT's with holes in the rad support for fog light wiring.