Yep, as noted, you have to take the elbow off, but otherwise it fits by lining up the tabs on the connectors with the corners of the bumper. Check the tightness of the end caps, I had one vibrate loose and go away somewhere in Nevada. At least the hose stayed inside!
Some people drill a hole in the bumper into the inside flange of the cap, and then use a piece of wire to pin it into place. There are also end caps available that have a push-in center that expands the size, so it grips the inside of the bumper better.
2012 Ford F-150 Eco, Max/Max
Jayco 26.5 RLS, Reese Sidewinder