@chris,
Drilling holes in the touch pad is safe if you drill in the right spots. It varies from model to model. What you want to do is peel up the bottom half of the touch pad to see where the leads are. Once you do this you can mark the safe zones on the front with pencil. You want to peel it up from the bottom, NOT from the top! I usually start at the bottom left or right corner.It can be tricky... you want to peel it up without cutting, cracking or scratching the material. I use a flat head screw driver to get it up a little then I use a credit card to get under there further.