Hi Dave,
You would loose all the configuration because it is stored in your old cluseter's repository profile.
There is no need to reinstall it. When your new cluster is ready, you would need to go to Server-> Configuration and Repository on your IPCCX server and re-run the setup. It will create a fresh profile in the DC Directory. Again, all your configuration would be lost. For instance, you would need to reconfigure JTAPI, ICD and Media subsystems, upload your scripts again, add application and triggers.
See it as a new installation with prompts and scripts already available for use.