@Dougl - My initial thought would be to use a fine tooth-hole saw. Lay the panel on a block of wood and align the outer edge of the hole saw and the semi-circle marking. Clean up the edge of the cut-out with some wet and dry sand paper.
I guess that's what is so good about this forum everyone has an opinion and shares thoughts/opinions freely ( in a respectful way). The other alternative is not worth thinking about IMHO.
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