I'm not familiar with your model, does it have a centralized control panel?
Our 5th wheel has the option to fill from the water connections, you just need to turn the bypass valves the right way, as shown on the decal in the controls area.
2010 Jayco Eagle 351RLSA
2011 Nissan Titan 4x4 (don't worry, I don't pull the Eagle with it!)
Currently shopping for a Silverado 3500 Duramax
Oh, and I have a tent... Somewhere around here....