Hi Eric,
Resin is an easy material to machine. I suggest using spade bits, used for drilling wood.
Use a thin piece of wood (ply or MDF) as a template, with the several holes already drilled.
Add another piece of wood under the resin, so as not to damage your work surface.
Clamp everything down well! Wear a mask, as there will be some dust.
Using drills for metal on holes that size can be tricky if the work is not held down.
Also, as the drill passes completely thru the material, it can either jam,
which is not cool for you 🙂 , or tear the material.
Have fun!
Richard