I've ripped out an old 70's fireplace to reveal the original Victorian opening. There is an infill of bricks which brick up the top half of the arch making the opening square which I plan on leaving in place. I want to cover the exposed brickwork inside the chimney breast with something. I've tried cleaning up the bricks using acid but some are damaged and would need to be chopped out, the cleaner wasnt that effective either. What and how would I go about lining the old brickwork. There isn't enough room to lay another course of newer bricks. Any ideas, thoughts or comments?