I realize this isn't as good a source as you use, Dane, maybe you can pull us up something from LULAC or Chavez.
From your SS admin.
http://www.ssa.gov/immigration/
Welcome to the United States and to Social Security! Whether you are a student or a teacher, a farmworker or a businessperson, a refugee or a temporary resident, if you are an immigrant, you have come to the right place. If English is not easy for you, ask us to find interpreters to help you. See our rules for people you choose to interpret for you. Use our Fax Catalog to order information over the phone and check out the Multi-Language Gateway website for Social Security information in 15 languages. We're here to help you.
The Social Security Administration (SSA) has a new process for noncitizens to apply for Social Security number (SSN) cards as part of the immigration process. Now, people age 18 and older applying for immigrant visas with the U.S. Department of State can also apply for SSN cards at the same time.
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United States/Mexico Totalization Agreement
... SSA logo: link to Social Security Online home UNITED STATES/MEXICO TOTALIZATION AGREEMENT. June 2004 (Printer Friendly Version) (Aquí en Español). ... www.ssa.gov/pressoffice/factsheets/USandMexico.htm
Crickets...