An interesting twist to this story....
I was able to get the horns to work (on both speakers).
Each horn has +/- connections on two sides (I'm not sure why). One of the things that I tried to do, was hook the wires to the other side of the horn ... that didn't help. My 7 year old daughter then suggested that I connect the positive wire on the terminal from one side, and the negative wire on the other terminal. Surprise! It worked! I did this on both speakers, and the horns worked on both. Just to make sure the fix really was as it seemed, I tried once again to connect the wires as they were originally and neither horn worked.
Unfortunately, the tweeter does not have the two separate terminal on it, so, there was no "quick fix" that I could do for them.
Does any of this make sense to anyone? Any other ideas of things that I might try?
Thanks!
Mark