I like this text personally. There is more to installing a fuel tank.
There are fuel lines, filters, filler spouts and vents. Ground wires.
There are also brackets to consider and ways to set the tank to
prevent water from setting under the tank and corroding the bottom of
the tank.

Incidentally, I purchased a new tank to install in my sailboat. The
regulations require a new boat builder to test the tank at 3psi with
soap bubbles. Seems like a good idea to me.

I bought a new filler spout from Attwood. I called them and inquired
about a test fixture so I could test the system to 3psi. They sent me
the test fitting for free at once. I sure liked that customer service.
I will probably test the system frequently. Can't hurt anything.

http://www.uscgboating.org/safety/boatbuilder/index.htm