If you do drill, try a small drill press. Riverstone.com has little
rubber pads you can use to keep things still, maybe the hardware store
would have them too I don't know. Drill presses don't tend to have the
rolling problem as much. There's a plate on the bottom that has a hole
so you can poke the drill through but this also serves to stabilize
round parts as they'll tend to settle in the depression.

Ingrid