Nicholas,
Your best bet is to setup up TACACS where you policies are centralized, do you plan on using an existing TACACS environment or would you need to build one from scratch?
You can run the ACS in a trial version for 90 days by downloading the product first, and if you need any help please PM and we can talk further.
When you configure TACACS the line tty and the number should be sent in a tacacs attribute where you can build permissions on which users groups can gain access. You can also join ACS to Active Directory, LDAP, or token server or you can use local accounts.
Thanks,
Tarik Admani
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