hybrid8- roll up the windows next time. also stops flooding in the car.

most of the heat is on the bottom of the unit. Mounting a fan under it will help greatly. You could hack a side vent in the chassis and blow a fan in the side if you wanted.

As with any electrical appliance, heat is a problem. A naturally ventilated empeg won't overheat. A confined one, next to a heater unit probably will.