I posted some pictures of a set of wooden mounts I used to make a "5-Holer" for the PVC pipes to sit in. I have the pictures on my home computer. I'll post later today when I get home.
They mount under the driver/passenger seats in that space that runs from one side to the other with access from the side under the passenger.
Sheree & Michael NCNG LTC(ret) with Munpi and Sheba (cat).
2016 Vegas 24.1 E350 5 speed "Ms. Enterprise", Bug-Guard Screen, Recliners, Infotainment Center, HUD, ARC Shower Rod, Safe-T-Plus, Curt SpareTire Mount,Tornado Black Tank Rinser, ext. WiFi Antenna, Roadmaster Tow Sys& Invisibrake.