Some of the Class A Customs Waste Water Tanks are built with a "lip" on the tank. Tanks can be hung by this lip, it is recommended to make a shelf to slide the tank lip into. You will need to brace the tank on all sides to prevent movement of the tank.
Brackets or Strap Systems
Due to the variety of installations we do not carry brackets or bracing systems. Do Not hang by ratchet strap, this is too thin and will not adequately support tank.
https://www.classacustoms.com/Bracing-and-Supporting-Water-Tanks_b_50.html