[Nick]

I have done this to a few of my pipes with good results. You can pretty much do it yourself unless you aren't comfortable with that. I usually use a 5/32 bit on the stummel into the bowl and a 9/64 on the stem. Idealy if it is a bent stem you would want to straighten it out the re bend it once you have drilled it. Also using a file on the stem instead of a drill is probably a bit safer and harder to F up.