Not sure if this applies, maybe just FYI.....Our 2007 PC originally had two 12V batteries in a slide-out tray. I had to ditch that battery tray to gain enough height to install two taller 6V AGM batteries. I replaced the tray with a flat plate and sides made of lengths of "L" perforated steel. Pictures are posted
HERE. Since the AGM batteries are sealed, there is no need for a slide-out tray.
Previously, I added a thick material rubber wall to protect the batteries from getting splashed from the rear tires. Pictures are posted
HERE.
I also made a splash shield for the propane tank on the left side, protecting it from the rear tires. Pictures are posted
HERE.