Index restore from retired server

I have a requirement to recover NDMP data from a retired Networker datazone to New server. I was able to scan NDMP tapes to media database and recovered index by "recover" from old index tapes. I tried Nsrck L6 as old server was running version  7.2.1 and new one 7.4.2. The savesets are still not browsable. There is EMC kb doc which describes using old server as alias of New and running Nsrck L7. I am yet to try this. How the index restore using recover and nsrck differs ? is there any way to make the index restored using recover browsable ?