Well I dumped in here late - the slowdown? But a couple of points.
1) Even though you never use tone controls, a 500K tone pot at "10" in a guitar is going to have some effect on the tone - like most everything "extra" it rolls some of the highs. You'll have to try it and see, but you may find you'll want to install a "fake" pot is she goes all icepicky on you. I think it's a resistor & a capacitor wired in parallel, but not for sure - there's info all over the place. I know it's really cheap, anyway. A whole lot of the famous Strat guys carry an old, cheap beater cord to record sessions, because if they do want less bite, the cord acts as a real long capacitor. I've played a few Telecasters with a "blower switch" - i.e. a switch that bypasses all the controls. Good God, throw a blanket over that amp!
2) It's really easy to make your own drill stops. If you start saving up dead ballpoint pens, pretty soon you'll have some nice rigid tubing, some caps, even the little inside tube that had the ink in it. Cut them up to various lengths, a couple of inches on down to half an inch. You can put these over a drill bit, and get pretty much goof-proof depth control. I have a little tin of maybe 20 of them, and you can fine-tune the depth by pulling the drill bit out a little bit.