I am trying to picture what you are saying about the BrassFlame you are looking at. Some don't have the tube on the top back but a double wall for the air to pass through but still have the side tubes coming out of the back wall and the tube still on the front. And if the stove has the front tube they almost always split out on the back side or ready to split out which is difficult to see from a picture or video.
Sometimes the back wall on the top has secondary air holes drilled in a row across the topside. Check the video again and see if you can see them. But some pictures would be helpful.
I am sending this picture again to show you what I am talking about. Those holes on the top back wall are original.
And yes, the bricks go on the sides of the holes so the tabs can hold them in place. The first BrassFlame I repaired had allot of ashes in the primary and secondary air intake on the bottom of the stove. To avoid the mess of ashes flying everywhere I hosed it with water before I started rebuilding it.
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