Every time I disconnect and reconnect the horn after it stops working it works again. Based on this my thoughts lead me to the relay, horn, or the wiring/leads that connect to the horn itself. Under the hood, you can hear the relay actuating (clicking) when the horn button on the steering wheel is pressed. This persists whether the horn functions or does not function at the time so relay seems fine. The horn works fine after it is reconnected "every time" so it seems the actual horn is OK. Which leaves the wiring/leads... I am going to see about buying the harness and/or leads for the horns connectors and solder/heat shrink wrap them in place. The area is a little tight so I will have to take the grill off before I can actually see if the leads have a short.

I'm a novice to put it mildly when it comes to this arena..., so it's quite possible that I simply don't understand the wire idea... Running a (jumper) wire directly to the horn won't provide any additional information about the horn itself in my estimation, so I am little confused by that suggestion, please enlighten me if I missed the point.

if you disconnect the two leads from the horn, and connect the jumper leads to the connector tabs on the horn (one from the battery (+) terminal and the other from the battery (-) terminal, you will be supplying
the horn with both power and ground directly, thus by-passing all of the rest of the circuitry
if the horn functions on a consistent basis by connecting the terminals directly to battery voltage and ground, then you can rule out the horn itself as the problem
i use simple single-wire test leads with an alligator clip fastened to each end
you will need two of these test leads
also, are you sure that all of your connections, especially at the horn terminals, are clean & tight?
a light scrubbing with a small wire brush or emery cloth and a light dose of WD40 on the horn connections is a good idea
most electrical problems are due to a poor connection