getting water from the fresh tank to the pump was a real problem. At first I thought I could just pass the tubes between the wheel well and the shower base. No soap!
This bath design has a seat. The panel under the seat slopes toward the wheel well, which pushes the sheet of supporting plywood back against the well. When you inspect the corner of the shower next to the wheel well, you find there isn't enough clearance to get PEX or vinyl tube through.
getting the front of the shower off was a problem. Once you remove the screws from the top piece of trim on inside, the top seems secure. It turns out that it's being retained by spring clips--you can remove it by using a suitable long piece of hard stock and hitting upward with a hammer.
The hower pan support rotates slightly, just enough to move the back edge away from the wheel well and provide enough room to saw off about 2". Once it's rotated back into position, you can snake the tubing through there with a little bit of an "S".
Why the vinyl and the PEX? First the vinyl is the feed from the fresh tank. The PEX going forward is for the drain. I wanted all the drain valves to be locted together in proximity to the tank drain. It also allows me to put the pressure relief valve up there, should I find the water pressure exceeding limits (a water pressure guage will be permanently insalled up near the drain, more on that later). The placement of this pressurized PEX line on the floor allows everything in back to drain down to floor level. A little dip of the nose and the floor pipes will also be drained--ready for cold weather!
When I reinstall the heating ducts, they won't have paths under the floor. The battery drain due to the heater fan just isn't worth it for me. I'll use it for space heat when it's cold, but once the weather is freezing, I go into a drained state and use bottled water for everything.
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