Not sure how yours is arranged, or what side it's on. On our 3121, I rerouted the black flush inlet to inside the wet bay. Another user, ATVer I believe, did a similar mod to his. There are some pictures in my photo album of the mod.
New Black Flush Inlet - My Photo Gallery
Our inlet was on the door side, which I thought was not so smart, being the tank outlet is on the driver's side. So, I just moved everything and made it look like it should have to begin with. FR even sent me a new sticker to ID what it was.