Hi
I have managed to fit one to my 1200.
It is not possible to wire it direct to the original wiring as the canbus system detects extra wattage draw and turns off that system.
It has to be wired through the supplied relay, it is necessary to dismantle the original plug and make up a small wiring loom for the new horn to work.
The only place I could find to mount the stebel horn was to make a bracket and hang it from the brace arm that fits from the steering head to the front of the frame using a u-bolt and a length of steel.
You have to watch how it mounts as not to interfere with the suspension and the brake line.
Nice and loud now.
Hope this helps.