Consolidate two domains

I have a server as a PDC in domain A with about 80 users account access the file sharing and print services. There are 8 servers with one as PDC and the rest are PDC in domain B. All my servers are operating in Windows NT 4.0 server with service pack 6. How can I dissolve the server in domain A and join the server as a BDC in domain B without lossing user account and file access right from the domain A? In addition that the server name should remain no change after the consolidation.