Well, not a smith, just an amateur- BUT
Drill press is good- so is a good PADDED vise to hold the receiver in the drill press. Some rifles really need a jig for drilling. Use a punch so bit does not walk. When tapping, use the drill press (unpowered) to hold the tap. Lotsa cutting fluid. Use the right taps (set of 3) when tapping a blind hole- or threads don't go all the way down. Learn several new swear words for when small tap snaps off in the hole. That's all I can think of, except don't try to D&T case hardened!
When tapping, cut for 1/4 turn, then back off half a turn to clear chips, turn forward 1/2 turn to get where you started, then cut 1/4 turn again etc.
You get in to a swing of it, forward 3/4, backward 1/2 turn.
Doing that I have never broken a tap, although everybody says it is just a matter of time until I do.
Absolutely use a punch to start it off, or it WILL wander.
supergluing the mount is also not a bad idea, use it as a drilling jig. Heat gun or hair dryer will break the superglue after.
Good points. Would add be sure that where you are drilling is NOT going to be somewhere you should NOT be drilling. Have seen attempts to D&T that drilled thru into chamber, barrel, blocks action, etc etc etc. Basically, a destroyed rifle. And having to learn a new swear word or two.