Quoted from Averell:
Original the Panel has three big rectangular holes.
The Problem is that the small LED reproduction will not work properly because the holes are too big.
I transmit the symbols from the Panel to the Board and cut out the outlines only.
That's why I consider to produce my own IJ jackpot LED board, with adjustable brightness, and more LED's at Ark area.
Normal cut out will work in case we have cover from backside. This is my plan: own jackpot board + decal.