I broke the nipple on my NA a year ago replacing the water pump. I drilled and tapped the hole, the fitting felt good going in but it seeped just a little coolant. I added som Teflon tape to the threads and it still leaked ever so slightly. I got tired of cleaning it up so I got a new tank. Don’t think I would try that fix again.
Smart decision, saving money is great but out in the middle of nowhere with a serious tank leak, you would pay a good few hundred bucks for a new tank.
Not so potentially serious was getting a new WS washer tank instead of fixing the old cracked one in my car. In my younger days I would have fixed it because it really was not a serious problem, taking the tank out is a pain in the butt.