That is my link , after I fixed the 'kink' it had decent pressure. But pump failed in the 3rd week of ownership. It was an Ardis.(think that is the spelling) I had it replaced with a shur-flo. Neither had adjustable pressure.
You can easily look behind the plastic bottom . find where the tank drains and unscrew a few screws and look inside with a flashlight.
It was a rainy few days at Algonquin Prov park...tarps kept us dry.
Wayne --Belle River (Windsor), Ontario
2013 Sunset Trail Reserve 25RB..
2015 White Chev Silverado 2500HD 4x4 (6.0 l gasser)
2003 Mountain Star 890SBRX Truck Camper