[60wag]

Working from memory.... The brass ring is mounted on the steering column. With the steering wheel removed, you should see the ring around the splined shaft than the wheel mounts on. The wheel has a little spring loaded plunger that is supposed to contact the ring. I guess the plunger wears down and shimming the ring up helps make contact. Once you've found the ring, try shorting the ring to the steering shaft. If the horn still doesn't work, you problem lies elswhere.