Elrey,
The heat was coming from behind the heater (or above). I tried the heater settings in a couple of different ways with the same result. Although not entirely safe I did apply pressure to the heater body and it seemed to reduce the output of hot air, I therefore thought it a "leak." I am planning on redoing the interior, including heat insulation, plugging holes and the like. I was just wondering if I need to remove the heater unit and seal behind it?
Stretch