Brian! LOL

I didn't mean to suggest the holes should be so big that you break the stock. :) But once done, the bedding compound is stronger than the stock, so don't worry that wood around the hole gets a little thin, as long as it doesn't snap when drilling it out and / or break the stock before the bedding compound sets. :)

But, yes, be careful and go slow. When you put a regular drill bit into the original hole, it can slip and twist in such a way that you can damage or crack the stock.