Mine is a little above the outlet. The pump instructions suggested a 12qn line to pump and 10an out of the pump. I spoke to manufacture of the pump and they asked ho from the tank. Advised 16". Was told no problem.

As far as leaks my trunk pan under the fuel cell is not sealed(fuel sometimes can get spilled when filling a tank) so noticing a leak is not a problem. I would see it just as easy as if it was mounted underneath.