OOPS !! Just realized I'm in the wrong forum! The info below pertains ONLY to the XII !! (consider that oops fixed- Forum Admin)
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I assume you bought the smaller version as I'm not sure the standard size will fit behind the lowers.
I mounted two of them - one on each side. There is a fairing frame bolt just to the rear of the standard horn mounting location. A simple straight bracket about an inch wide and maybe 3 inches long will mount to the bolt and let you swivel the horn so that it will comfortably 'nest' behind the lowers.
Be sure to use a relay and some heavy wire as these horns will draw a pretty high amperage and you may as well get all you can out of them.
Ohio Mike
Stebel horn on 1200 Voyager
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