There have been a few posts on this but...
I bought an adjustable hole saw off ebay for like $20 and it worked fine. I had to resharpen the cutting knives after each hole, but still a clean cut. Undersize the hole a little and then use a dremel with a sanding disk to make it perfect.
I too used a hole saw actually three hole saws, for 5", 3 3/8", and 2 5/8", all undersized and finished to exact size with a drum sanding kit I bought at Harbor Freight for cheap. First I scribed the hole location with a pair of dividers on the front side of the dash, and sanded exactly to the line. Used a drill press and low speed. Came out perfect, but be careful, you only have one attempt on each hole. Measure three times and cut once. Rick
S/D, sure you can use the aluminum dash as a template, but be aware that the CF dash may not be the exact same dimensions as the aluminum one. Mine was about 3/4" shorter in height, FFR only knows why.
I would advise against gluing/sandwitching the two together. The two materials will have different temperature expansion rates and may cause them to delaminate. If you want to make it stronger (I did), add a layer of fiberglass before you cut the holes. If you want it even stronger (I did), bond a bar of aluminum to the bottom. This is also give you something to mount braces to.
You also asked about mounting a guage to the left of the steering wheel. That depends on the size of the guage, if it's a 5" unit like mine, no it won't fit, at least not well.
I would also second the notion of cutting the holes a bit small and use a sanding drum to finish off the bigger holes and a dremel tool for the smaller ones.
If you want to laminate the CF to an aluminum panel (I did)it's best to use 1/32 inch double coated foam tape 6-9 inches wide.
Clamp the two with pieces of 1 x 4 and let stand for a day or so and you will have an absolutely tight laminate.
Drill the panel from the aluminum side and wear a protective breathing mask,as the CF dust is NASTY stuff to inhale.
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