Same thing happened when I had my 2000. It's an easy fix, but its kinda hard to explain..
Take off the nut and thread (yellow circle)
Once it is off, get a couple washers that are significantly bigger than the hole (red circle) but make sure the thread is able to go through the washers.
You will have to go under the car to do this and will need an extra hand.
Put the washers in-between the body of the car, and above the broken off part (black circle)
Have someone from above thread that nut on.
From below, hold the broken off threaded piece with a pair of pliers.
Have the other person in the car tighten the nut down until it is snug.
The idea is to wedge the washers between the body and the broken piece so it does not pull out when you lift up on the brake.
This beats having to weld it back in place.
Let me know if you have any questions.
Hope this helps.
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