polished alum. sill plates anodized?

Hello,Does anybody know whether the original late 60s,early 70s sill plates are anodized by the factory?I'm trying to restore mine,having sanded them down,avoiding removing the tread grooves,and then polishing,buffing them.They came out darn nice,not new,but nice.I can wax them now,but I think they are going to get scratched up again.I could go to a rechromer shop and have them anodized. Thanks for any suggestions. PS I know they sell repops,but I wanted to stay with the originals,since they were in such good shape.