So Kevin... are you saying that the 5 sided box and the dutch oven would work in a similar way? For example, that a dutch oven needs those coals on top, so also the 5 sided box would?
If so, that does make sense. I wonder though... if I could get the temperature in the box up to maybe 400 degrees without using the coals on top just by convection (and some radiation) from the stovetop surface...
So long as the top was well insulated... maybe?
This might be one for experimenting with. With a built in oven thermometer and rack, you could do breads and wood fired pizza... WOW!
As a note to the original post/question: You have a cool Brent Swain designed metal boat, so I'm assuming you know your way around a welder? Maybe give our whacky oven idea a try?