Sorry guys, seems like I don't get notifications of replies anymore. I'll try to answer some questions...
Smoker57, I used two 1/8-1/4" steel bars over the pipe to support the blocks above it. Once mortared in it worked perfectly.
Agdrillman55, I haven't built a baffle for it yet but I'm able to control temps with the size of the fire. It's not perfect, but it works. The lowest temps I get depends on the ambient temp. The smokehouse isn't insulated. I've had no problems keeping it at 70°F on cold days here in Texas.
End disabled vet, I chose the bricks over the blocks for the firebox so I could make the firebox smaller, and I think it looks better too. I could have used cement blocks. The white bricks are fire brick.
I don't put a fire directly in the smokehouse. The fire in the firebox can easily get the smokehouse temps to over 200°
I planned for this to be a cold and hot smokehouse, but I can only use it as a cold smokehouse during cooler weather.
I sealed the pipe at the firebox with fire clay. And used mortar at the smokehouse.
I lined each side of the pipe with cement blocks and covered the pipe with dirt.