Can a GLM Water/Fuel Separator Kit be installed above the fuel tank on an I/O. The easiest install location is above the fuel tank, a little higher than the engine. The engine would be to the left of the fuel tank and the fuel to engine line is a down slope all the way to the engine fuel pump. This is a carborated Mercruiser 110 4cyl inline. Would I need a check valv e between the filter and the tank to prevent fuel draining from the filter feed line?