dont see why that wouldn't work, less complicated is always good.
I am going to chalk it out today on the patio concrete pad. Should be able to build it without mortar. It is cold now in Wisconsin. I will use a few dabs of high-temperature silicone to keep things from shifting. Fill the blocks with sand for insulation. Leave a hole about halfway up in the center for the chimney on the opposite side of the firebox. Fill the chimney gaps with high-temperature foam. Not sure if I will stucco or some other treatment on the outside of the smoker for aesthetic reasons. That will be the spring decision.
Fire brick lining the interior of the firebox.
Angle iron screwed with tapcon screws for the interior supports of the cooking grates. For grates, I may advertise on Facebook for someone who is throwing away a range/oven.
Expanded metal on supports for the firebox grate with a 6-inch gap on the bottom for ashes. Removal from the top. Flat steel stock 1/4 inch on the top of the firebox is removable for maintenance. Also supports in the firebox for a grilling grate in case of charbroiling steak, burgers, and other tasty foods.
Works out great in the winter as one of my friends is off from an agricultural career during the winter. He has excellent metal fabrication skills. He was a super club chief and has his own custom-built wood burner offset smoker on a trailer.
This build will supplement my first smoker, a Traeger 650 ironwood. The pellet smoker will be used for shorter smokes such as veggies, pork ribs, chicken, mac and cheese, pineapples, and other delicious foods The vertical block is one for briskets, pulled pork, cold smokes, whole fish (carp, catfish, Great Lakes salmon), and larger guest lists cooks.
When I finish I will post pictures of my patio setup.