Convection Plate - For an OKJ Longhorn

Camp Chef , 37 x 16 inch cast iron griddle top, I'm gonna give this a try with the colder weather, I figure butt this up against the heat source/ fire box area, it will get a nice even heat across my Royal Oak Off set, which is 40 x 20 . So it will fit in nicely below the cooking grate.

My temp range is from top  thermometer area of the barrel to cooking grate is 50*degrees, sometimes 75* degrees/ with a 50* degree difference from heat side to exhaust side. 

We will see what happens, I don't have fabrication resources, so this is what I think makes sense, Plus its a great piece of cast iron to make a crap load of pancakes, eggs, and smoked sausage for breakfast outing.