Get a 2 feet tall 13 by 13 ceramic flue pipe and set it on top of the angle bar and the back side of the fireplace.
Build your own backyard fireplace.
Set an angle bar across the fireplace interior.
Bricks gravel a stake a tape measure a string or tine a trowel and a large shovel a level and a tamp.
Cover the holes on either side of the ceramic pipe with firebricks or concrete blocks.
I have been wanting to build a diy fire pit in my backyard for the longest time.
Use some fire clay to seal the holes and spaces on the smoke chamber roof.