I have repaired my refractory panel cracks with furnace cement and am about to repair them again. Inquired from a vendor about replacement panel to find out replacement cost for all panels exceeded $500 Question: Can you replace the refractory with firebrick? I preceive no logical reason why replacement cannot be accomplished in this manner. The function of the interior surface would be enhanced by using a more solid 'firebrick'.....I think. I have a buddy who is a qualified mason who can guide me through the project. I attached the FP ID Plate for info. Thanks, BW