Eagle Cap quality?

We had an Adventurer 80RB and while we really liked the camper, mostly for the floor plan and interior, we had a major problem with the grey tank install from the factory. To complicate matters, the black & grey tanks were only 5 gallons each. I get that as it is an effort to reduce weight. The problem is that since the first time we emptied the grey tank, the panel indicator showed 1/3 full afterward. I thought this strange as it was unlikely that the sensor was dirty since it was a grey tank and never been used before. We found that the tank would easily fill up within a day of conservative usage. We'd empty the tank and it always showed 1/3 full afterward. As I looked into it, I discovered that the tank had been installed at an angle with the outlet pointing up slightly. If I drove the truck up onto the leveling ramps with the front wheels, it would tilt the truck sufficiently to drain the entire tank. This was a HUGE inconvenience. We basically had to live with a 3.5 gallon grey tank. It was extremely tight in the compartment and no way for me to affect an adjustment without major surgery.