Then I don't see how they failed. All that's needed is an appropriate heater (ceramic disk, for safety) and an extension cord. It could be run in through a window, using foam pipe wrap to block the rest of the 'window gap'. The heater should be placed on the front passenger floor, with at least 2' clearance in front and 6" behind and to the sides, and set to Low heat.
you'd have to go back to the thread from last winter. i don't remember exactly, but i think it was more work than it was worth because the car cooled down so fast after leaving.
