Good approach. Well done. In my extended 350HD dually, when my raised bed is in place, I still have plenty of room behind the bed to the back door to hold 3 bicycles. I just pull the front wheels, and stack them upright using blankets to cushion them. With 1 to 3 bikes cushioned in place, they don't move around and I save having to purchase a mount and make a mounting bracket like you did. When I have to carry more than a few bicycles, I put a rack on the back.