Siren Speaker mounted to Front Crossbrace
The full-size, 100 watt siren speaker. I dislike the sound from compact speakers, so I went with the full-size. Fortunately I have room to mount it.
The Focus's main bumper is a rectangular tube of high-strength steel. 4 pilot holes were drilled, then tapped. The siren's bracket was then mounted with machine screws and lock washers.