Another small fan underneath it? Maybe one of those small fans made to fit a PCI opening on the back of your computer would work there, one like this. Or maybe moving the fans you have now from the top to the side to blow air over the top and bottom would do the trick? I never thought to check the underside of the ESC, I'll be checking mine next run after I replace a broken camber link. Maybe this time my Pede has learned now that the curb is always gonna win.:D