Getting ready to do a clean up on my brick self serve bay walls and had a few questions. I will be using some type of HF acid (nu wall or equivalent) and my question is will this product damage my in bay signage? My signs are a combination of aluminum with vinyl graphics and plastic Kleen Rite type. I did a rehab on this wash and the first time I cleaned it the bays were completely stripped down is why I ask. Also wondering if applying a sealer to the brick would make it stay clean longer or possibly make it easier to clean. Thanks!