So far no problems. Plan to make this a permanent change. Thanks for the input. 
I am looking to do this on a Grid Iron and was wondering how you decided on 9 x 9 for the ss plate.
Just seemed like a good (guesstimated) choice. Worked out well. First thing I noted on observation with drip pan removed, was that the flames no longer arced downward from under the flat deflector. I had noted that the original domed deflector had arced flames downward and probably increased the heat on the bottom. Also the support arms of the dome, created a directional pattern, that increased heat distribution to the effected area. IMO. It all worked out well. I also wonder if I had just used the fire brick alone, that it would have resolved the issue as well. NOTE: If you remove the domed deflector and replace as I did, be sure to block the two holes in the auger housing so you don't lose air flow to the pot. Let me know if you proceed.