Don't bother. The brake light switch on 1999 beetles (maybe all of them, actually) have been recalled. Unless you get it changed, the brake lights will keep going out. Call your local dealer and they...
you have to open the trunk and behind the carpet you have to pull off, and then unscrew the bolt and push in the sides to open and then you will see a light bulb and then replace it.
Open the trunk, inside there is a panel that you have to remove in front of the tail lamp. Inside that hole is a star like screw, unscrew it all the way off. Use a flat butter knife to pry the tail...
if u want to know how to chang brake light in the trunk theres the rug pull it back and u will find the back of the tail lights twist the light socket n it will come out