This authorization is granted solely to complete the transactions above. The first step is to download the template document from the SSS website and then print it.You should fill it appropriately. Permanent residents are issued a valid Permanent Resident Card (Form. 551) as proof of their legal status in the United States. SSS Authorization Letter is a document for authorizing an individual on your behalf to transact with the Social Security System. I have directed that a Best Financial Management Practices Review be conducted of the Wakulla County. The process of becoming a U.S. citizen is called naturalization. LN - The student is Limited English Proficient and is not enrolled in classes specifically designed for LEP students.