66 Horn Contact Nightmare - Please Help!

I have a 66 GT Fastback that I just got through restoring and I am beating my head against a wall with a horn issue. My original turn signal switch wasn't working (horn was working fine), so I replaced the whole assembly with a reproduction unit. The installation went fine and everything seemed to fit well. The turn signals worked, so I reinstalled the wheel (Grant wood wheel) and the horn worked OK as well. But when I turned the wheel a few times, it made a terrible grinding sound. I took the wheel back off and I found that the top horn contact had just been mangled and rolled over, rendering the horn inoperative. At first I thought that I had screwed up the reinstallation of the turn signal cam (which I had to remove), so I coughed up another $30 for another turn signal switch and bought a new Grant wheel installation kit (just to be safe). I reinstalled the new switch and used the Grant turn signal cancellation pins from the new kit instead of the original turn signal cam because the positioning of these pins is "foolproof". Needless to say I thought I had it licked. The installation went smooth. Everything seemed to be OK, until I turned the wheel again and "crunch". Scratch one more horn contact! Has anyone else run into this, and if so, what the heck can I do about it! I've had to clip the contact off and tape up the hot wire just so I can drive the car without a shower of sparks everywhere. Any help anyone has will be greatly appreciated!

Thanks.

Thanks for the reply. I didn't forget to install it, but I have had trouble getting that spring centered on the steering input shaft. Do you know how far that spring is supposed to sit on the input shaft? I can pull the shaft over a bit and get the spring to drop down around the shaft, but it just doesn't feel right. You're probably right about that being the source of my problems, but I just can't figure out what I need to do about it.