Windows NT server and 2000 server AD

I have just installed a new Windows 2000 domain/AD server. I want to rebuild one of my old NT servers as an NT 4.0 Server in the same domain as the Windows 2000 server. What server type should I make the NT server? Any other
issues? I want to usethe user info from the 2000 server and build NT from scratch. Thanks for reply.
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