I am leaning towards buying another Woodstock Palladian or Keystone for our upstairs, and I am trying to finalize the location. Right now the corner looks pretty good. The WS installation info says that if I use the rear heat shields for the stove and pipe, I need twelve inches' clearance from the stove corners to combustible walls. Can anybody tell me if the 12 inches is good for both rear and top vent, or is it only good for the top vent?