Mucho patient heating and scraping of paint, primer and bondo, has revealed a 15/16" hole cut in the OS scuttle, with a slot cut horizontally, about 1/4 x 1/8 each side, so the end result is shaped like a London Underground sign.
Is this any of Jeeps doing, or a PO bodge

It's hard to tell with all the bondo etc, whether this has been cut in or pierced when the panel was pressed.
It wasn't done at the last tart up.
Someone had stuffed a 1/4 penny washer behind the hole, and glued it on with bondo.