Woody,
My handy/dandy picture shows this; Using the link you supplied of the horn relay, and in that same orientation, the far left tab is the horn button on the column, the center tab is BATT and the tab on the far right goes to the horn.
You can prove this with a small battery charger. Connect the positive cable to the center tab with a small wire. Connect the ground to the case of the relay with a small wire. Use a screwdriver or small wire to jump from the far left terminal to the case. This should make the relay go 'click,click'.
If the relay melts or your garage burns down, Denny Graham told me he would pick up the tab for repairs.
Stuart
