My '95 GL had the whole airbag and horn assembly come loose as well. It was not anything inside of the airbag unit. It was the WHOLE UNIT.
There are two TORX

screws (or what-ever you'd call them) behind the steering wheel. You have to turn the wheel about 90 degrees one way to get to one and then turn it 90 dgrees the other way to get to the other.
You could actually shake the whole airbag and horn assembly around!
This happened at less than 60K.
After I tightened them it has stayed in place for another 106K miles!
Personlly, I would dare open the actual airbag assembly! Those things scare me! Good luck!
DB