The real problem with gauges for the LPG is that what you can actually get out of it is dependent on the temperature. The colder it gets the less you will get from the tank. I will admit that I have gauges on mine, but I really have not figured out how the gauges react to cold temps. We are going to find out in March.
2013 Infinity 3640RL with Trailair pin box
2008 F-250 King Ranch Power Stroke diesel with B&W Companion Slider hitch