Hi, I have my dad's old car club plaque from the late 50s or early 60s. Unfortunately, it sat in a box that some fertilizer was spilled and it ate up the metal a bit. I had to grind down the residual fertilizer to keep it from destroying more metal because I could not completely get it all off. So, I have a couple of questions. First, can the metal be "replaced"? Second, do I paint the plaque first then have it polished or, vice versa?