HSS Drill bits worked well for me. Higher speed, light pressure, let the drill bit feed itself. Then lightly chamfer your holes. Oh, and use nylon fasteners…
Yes you would be better with proper tools if you want to do yourself a favour.
Zero rake ground bits reduces stressing the material.
See the link below : number-sizes
Buy made in America also available at Aircraft Spruce and the like.
I was told that after drilling the holes and shaping (for countersunk bolts) the sheets should be cured thermally in an oven. I did so with my second set of head light covers and had no more problems with cracks (developing some time after installation). Not sure if the use of zero-rake ground bits makes this obsolete?
Zero rake prevents the drill from sucking itself into the material being drilled, therefore damaging the Acrylic. The same needs to be done when drilling brass.
You can get away with it if you have very light feed rate and crossed fingers.