I plan on using some expandable foam to fill some cavity space and keep the aluminum edges of the cell box away from the cell walls. As for the alluded surge tank valves, could someone please explain what needs to be controlled and the type of valve used. For clarification, Greg G. you were having problems when the return line was returning aerated fuel to the surge tank and the surge tank pickup line was drawing from this region of aeration? Or was this in the fuel cell?