so the neo is outand the installer wants to put in a cabello 1200. I would rather do 1700. Heres only hang up i have i took all fire brick out of old fireplace. It was in bad shape and i plan to roxul sides anyway. Not drpthe enviro says i need 22 3/4 inch i only have 22 1/2 but i want to reface my brick on fireplace face. So i would need another half inch but how close can i get to back wall? It is all masonary and the chimney wall goes to my closed in 3 season room. So warm bricks would keep that room nice.