With my permission the installer ran the lines through a "Y" so I have just the one Schrader valve. He put it on the rear wall of the battery compartment {on the drivers side about 6' aft of the front wheel} on my 24' Class C. It is protected from the weather and road debris and easy to access.
I keep about 15 psi in the bags running empty/light or when it is just sitting in storage {that recommendation came directly from Airlift so the bags hold their shape better} but add 50# when I load up the cargo trailer with my Rzr our motorcycle. With 2,600# of loaded trailer attached this keeps my 10' cargo trailer dead level. Works for me.
:C