Tim,
Wow! why so far back? You realize EV 5 has meet its End of Life, right? :)
Basically it is this.
1. Back Up your Vault Server data, indexes, and SQL Databases.
2. Stop IIS Admin Service, and all dependent services.
3. Stop The EV Admin service and all dependent services (This will include all Vault services under it)
4. Run setup.exe from the Server Directory (Typically the \EnterpriseVault\Server folder)
5. Normally the server does not need to be rebooted after installation, but if it asks you to,
that is because of the environment.
6. Restart services in this order:
IIS Admin (followed by the dependent services that were stopped)
Vault Admin Service
Vault Directory Service
Vault Index Service
If you have the EV 5 sp5 binaries you will see a documentation folder in the path */Enterprise Vault 5.0 SP5/Documentation. Open the SnapIn.chm and it has a section called Upgrading to Enterprise Vault 5.0.
I highly recommend getting to EV 6, 7, or 2007 asap. :)
Regards,