There a couple free e-books online as well about sidecar riding. Someone else probably has the links handy. I don't know the Bonnie history well enough to talk about years. It's all about the frame. I've seen plenty mounted on 2004 Bonnies though so that should be no problem. Any of the tubs you mentioned should mount fine to the Bonnie and you can see examples of all these in the photo thread. The Watsonians are EXPENSIVE ($5k to $8k) . The Ural tubs are WAYYYY cheaper. This guy has a Ural tub on his Bonnie https://sites.google.com/site/threewheelbonnie/Home I believe RTR means ready to run, meaning no work needed, bike with sidecar ready to go. Cozzi (the installer) installs Cozy (the brand) sidecars. He doesn't make them, just installs. Similar name. All the options mentioned (Ural, Triumph, Cozy, Watsonian) would meet your basic needs. It's just a matter of price, looks, and ergonomics. Mounting a chair is not a simple thing and you should definitely consult a builder with experience or have them do it for you.