I have the KSH 50 gallon with tool box.
I've had it installed in 3 different trucks so far, 2006 Ford, 2011 & 2016 RAM. Other 2 trucks I used a pump, this time I'm doing gravity feed.
When I installed it into the 2016 RAM, I needed a bigger Y pipe to cut into the factory fill neck. I called KSH and they said just use the 2.5 inch Y that I had, make the clamp tighter. But I need a 2.75 inch Y pipe.
So I called RDS and got their install kit and used it. Its the correct size Y pipe.
I have a NAPA Gold inline filter in the tubing from the tank to the Y pipe.
Good quality tank, its almost 10 years old and still working fine.