On my 23B hybrid, the spigot is behind the drivers side rear wheel (tandem axle) mounted to a bracket screwed to the bottom flange of the frame rail. It is white in color and has a length of Tygon tubing that goes over to the low point on the fresh water tank. The official "low point drains" are located on the same side but about 3 feet aft of the tank drain. They are black and just poke through the flooring material and you have to open them from inside the door at the bottom of the bathroom vanity cabinet.
2006 23B Hybrid with 10k round bar WDH
2011 F150 4x4 SCREW Ecoboost, Max Tow, Integrated TBC, 3.73 LS axle, Firestone Ride Rite airbags.