Hi,
Since the instrument panel is flat, and the Carbon face primarily for cosmetics (The look!

) Then Definitely just resin infuse a big enough flat panel in 4 layers of CF on a glass plate .. use Pro-finish for the outer (front) layer to keep a good straight weave pattern- You can use Glassfibre as layers in the middle for desired thickness, just make the outer layer at least two layers of CF-
Then cut out the holes using a set of new sharp holesaw blades, slightly smaller than the finishes size .. Sand the holes to a perfect edge finish ..
Don't bother to buy a high quality holesaw, just a few holes cut in CF/Glass will dull the blade ..
If you tape the surface of the CF, and you are careful, you can easily cut the holes without the Infusion resin chipping ..
If you have some skill with a jigsaw, buy a permagrit/tungsten-carbide jigsaw blade and use that ... remember the tape on the CF face--
Believe me .. its MUCH easier than trying to get a nice pattern by trying to get the CF to "go around" "plugs" for the holes --
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