IMHO this is a poor choice float to be specified for a moving vehicle application on a LARGE tank. While waterbox application sloshing seems to be minimal, the wave action in a large tank can be severe.
My dad and I built a large stainless steel combo solution and recovery tank for one of our Banes over twenty years ago. We used a very simple float shutoff enclosed in a perforated 4" PVC pipe mounted vertically. It worked flawlessly. I still have it.
Thanks,
Lee