When we remodeled our camper we were going to need some batteries and additional propane (LPG) tanks for extended camping trips. I removed the existing hardware for the single battery and single LPG tank and re-engineered the set-up.
I started by installing the batteries and hardware. Then I installed dual LPG hardware and tanks.
Above: Because of the shape of the front of the camper, and the need for the box to be as close to the camper body, to allow room for the propane tanks, the battery box is oriented to open out from the camper body.
Next step was to bolt a dual propane bottle tray to the frame in front of the battery box.
Above: This regulator automatically switches tanks when the first one runs empty. Very convenient if the first tank runs out of LPG in the middle of the night. It also has a gauge at the top to let you know when the first tank is empty.