Your fuel tank company sounds incompetent.
Electric pumps are "pushers"NOT pullers.Vapor in a pump a couple of feet from the tank and away from the"real" heat?BULLCRAP!!!!
That pump would have to be hotter than a $2 pistol to effect fuel temps.
But in any event,a return line solves multiple issues.It re-circulates fuel(thus cooling it.The circulating fuel keeps the pump cool(er).And a return line keeps the pump from"dead-heading".(please no Jerry Garcia jokes)
And racer X-how about coming up with a solution other than "pay someone else to fix it"?