The bike is mounted to a piece of 1/8" plate steel with 3 hydraulic pipe clamps, it ain't going nowhere. The tires are strapped on top of the frame.
The bike only sticks out about 2 ft. behind the motorcycle. The view from the mirrors is unobstructed, as are the lights.
The risers are 1/8" aluminum angle, they are bolted to the frame at the rear passenger foot peg. The top is made from 1/8" plate steel and is bolted down to a frame extension that I usually use for my trunk. It was welded on the back of my bike a few years ago when I worked at one of the sign shops.