You need ssn card proof that he lives in texas so insurance statement or a copy of the plan with his address on it an you also need his birth certificate for proof that he lives here in texas you can look on the dmv website to look at all the excerpted documents they will accept the are picky about it too i know they will take the ones above if he owns a house or rents and has a copy of the lease or title you can take that
I'm not sure about the office I Plano but the office in McKinney has the option to schedule an appointment that could make the process easier.
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