Nice job! A place for everything feels good.
I just added one of these same tubes to my camper today, too!
I have a 22rb 28' camper. I couldn't find any under frame rails to mount it, so I simply attached it under my bumper. I used heavy duty zip ties for the time being. Eventually I'm going to get some stainless steel cable ties to replace them. I have one trip left this season, so it'll be fine for now. I didn't like keeping the hose in my bumper and I didn't like my front passthrough littered with an extra big tote bin, to store the hose. It was nice to store it in the new tube. Then, I took my black water flush hose folded it in half and stowed that in the bumper.
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2022
Jay Feather 22rb
2023
Ford F-150 SuperCrew 2.7L EcoBoost, 4x4, 3.73 axle, #1900 payload #10,100 tow capacity
Timbren Rear Suspension Enhancement
Eaz-lift Recurve6 W/D