A potential "fail" scenario; You get the remains of the old bleeder out, but you had to drill so large that the threads are gibbled and the new bleeder wobbles around in the thread and does not seal.

Never fear! You can bleed it using the new bleeder. Then, remove the new bleeder. The brake fluid seeping through the system will preserve the airless state of the caliper for a few moments. Drop in a ball bearing of appropriate size. Hold it there with a short bolt, same size thread as the bleeder (short enough that it does not foul the wheel). The ball will seal against the taper in the caliper.

It is a really ugly solution, but it is very effective. If you have to bleed it again in the future, the ball can be removed with a magnet. My Jaguar has been running for two years this way.

Andrew