We recently purchased 2 Stebel Nautilus horns, one for the Vulcan and one for the Concours. I tackled the Vulcan 1st as this install was a little more straightforward as far as mounting it goes. The Connie will require a lot of fairing removal and I'm simply not up for it this weekend.
I made a bracket out of a straight aluminum bar that attaches to the front engine mount bolts, and extends upwards to have the horn mount between the ignition switch/choke knob and the shifter. It is LOUD! I used my ear protectors I wear when I'm using the table saw or other loud tool, and it still blasted me out!
Here's a pic:
And here's a short clip of how it sounds- listen to my dogs go nuts lol!