A while back my horn quit working.  One day it worked, the next day it didn't. Ground wire in the column was good, but the power wire had no power.  All the fuses are good, so I pulled the steering wheel.  When I got to the turn signal/other/ rat's nest I found a dusting of copper everywhere in that cavity.  Then I noticed that the copper "bump" for the horn power (on the spring loaded contact) was completely, smoothly sheared off.  The bump on the ground contact was fine.  I guess the power line wasn't making any contact with the horn rotator thingy, because the contact in the turn signal apparatus had power.

Here are my questions:
1) Anybody else had this problem, and how did you fix it? Is there a solution short of totally replacing the turn signal harness (I've already done that once and don't want to go through that again, if possible)?
1b) I do have the old harness and one of the spring contacts (yes, the ground wire contact) for the horn is still good (the power one broke--that's why I replaced the harness), but I can't figure out how to remove it from the plastic housing without simply ripping all the  housing away. Any help?
2) Guesses as to why the power tit wore off but the ground one didn't?