Turtle,
I agree with Cam,
Don't feel too bad, I not only broke the first one I attempted to fix but then proceeded to snap
a bolt on another bike several years AFTER I thought I learned my lesson
I ponyied up for an OEM replacement.....$80.00
I have also gotten the snapped out bolt retrieved from the tower just like cam said.
Drilled with a reverse bit, got it far enough out of the tower, only to find it spun out with finger power the rest of the way.
My best buddy snapped off a tower trying to hold back the basket with a breaker bar and binkk! off popped his tower. he ran a bolt and nut through it and the one opposite it
(for some semblance of balance) and has been running it for 5yrs now.
Tuck\o/