Install named instance of SQL Server 2000 on existing Windows 2003 server in cluster. Help!

Hello,
I need to install a sql server 2000 named instance on a machine that is already running sql server 2000 in a cluster. The newly installed named instance does not have to be in the cluster (preferibly not).
Setup:
I have 2 windows 2003 hosts with SQL Servel 2000 in a cluster. Server1SQL1 and Server2SQL2 (Server 1 and 2 are of course virtual server names created on the real servers, RealServer1 and RealServer2).
I need a new named instance Server1SQL3.
How can I do this?.
I have read quite a bit of info on installing named instances on clusters, but all documents describe how to add the new instance to the cluster, wich I dont want.
It would be acceptable to have to install a new virtual server name (with its own IP) on RealServer1 to have something like Server3SQL3.
Is this possible ?
I would appreciate any help and/or indications you could give.
Thanks,
Mark.