Train horn installation location

Hi,
I am attempting to install a hornblasters air horn kit on my 97 F250. I’m to figure out where to install the air horn itself, since it’s pretty big. Maybe this is a stupid question, but is there any reason I couldn’t mount it on the passenger side outer frame rail? Is this a fuel line running along here and is there any reason I couldn’t mount anything near that? Also, can I drill into my frame or is that a poor idea? Open to suggestions on anything!

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Installing it in this area with work great we see a lot of customers with that style of horn “mother trucker, safety, tug” install it in that location against the frame. So you have to drill as few holes as possible I would try to at least line up one of the mounting holes on the horn with one already on the frame.