My husband and I are in the process of renovating a 113 year old farm house. Recently a friend mentioned she had some some old tin ceiling tiles that had been taken from the demolition of an old local bank, and we'd love to refinish them and install some in our home. The trouble is they are very rusted. What is the best way to remove the rust from the tin tiles, and also after the rust is removed what should we us on the tiles , if anything????