Air horns...

Above is a shot of one of the horns, mounted under the gas tank on the left-hand side.

Above is a shot of the other horn, mounted under the gas tank on the right-hand side. You'll notice the aux. horn relay just above the horn and in front of the tank. The coil of this relay is powered by the original horn wiring, and 12 vdc from the battery is routed through its contacts to the air compressor.

Above is a shot of the air compressor, mounted inside of the right-hand side cover. This is an unused compartment, and worked well to hide the compressor.