Does anyone know the process we need to get permission from the FDIC to convert the membership slogan to Spanish? I don't readily find anyone in their website that is referred to.

I am not sure what you mean by the "membership slogan", but I think you can get all the FDIC notices (the stickers for the front door of the branches that say Member FDIC)in Spanish just as you would in English. Our bank, although in Puerto Rico, has the signage in English as does the competitor's branch next door. I know I have seen them in Spanish, though.