We are using a childs wagon as the base for a parade float. The float will be decorated to look like a canoe. We want to attach "waves" to the wheels so that they move up and down as the wheels roll down the road. Similar to this: http://www.skiptomylou.org/2011/07/05/fourth-of-july-float-2011/ What kind of joint would we use? Thanks in advance for any help.