OK, so I created a new setup with a thicker hearth. The idea is to lower the temps to around 800F or so instead of the 1000F I got with the first set up.
The 2nd change I made was that I allowed for a bigger gap around most of the bottom stone to allow more hot air into the oven chamber. I'm still keeping the walls of the mini oven up with the purpose of trapping the rising hot air slowling it's dissapation into the larger upper dome of the oven.
3rd change I made was to add a pizza pan to the ceiling and a few bricks. The idea is to help the ceiling reflect more heat. With the first setup some of the rising heat was transferring through the 3/4" stone above thus defeating one of my intended goals of getting the temp above the pie to 850F.
I also tried to place the lump coal in a U shape pattern towards the back of the Primo Firebox to hopefully influence the way the flames would rise. I want their to be more flames and heat to the perimeter rather than straight up the middle. Remember, I no longer having issues getting the hearth temps up. I can reliably get hearth temps up to 950+. As a matter of fact, it's too much heat. I never imagine with I would have an issue with too high of a hearth temp.
So here's the new set up. The distance between the hearth and the ceiling is now 2.5"+. The hearth is about 1.75" thick.
Last pic shows the direction of smoke (and ultimately heat) travel. From the back to the front.