Showing a left hand blower setup. Air will blow out opening on right tube.
Showing a Right Hand Blower Set UP
The pleum is 3″ thick.. (the 11 x 18.25 part in back ) the front bar extends from 36″ to 52″. At most you want the opening to be 50″ wide to allow room for the doors if applicable to be on top. Also the depth is min 16.5″ and extends to 26″. For firebox deeper than 26″ this will still work fine. Black bar in front is appx. 1 1/4″ tall and 3″ thick.. Air flows from blower through one tube, through back and out other tube.