The 2 Mobile Suites I've had had 2 gauges; the off door/kitchen slide is heavier than the door side and the pressure used is 10psi higher on the off door side. It should be a relatively easy fix to add a separate line and gauge or don't use a gauge just a tire gauge to adjust the one. Before you do this, with the rig loaded as normal, check the air bags for proper adjustment. The 2 plates that the air bags are mounted on should be basically parallel when inflated (about 5 1/4 inch apart, IIRC). If they are pretty close to this it should work ok.