Hi,
To answer your question....
1. will I be able to uninstall the SAV from the client pc's cleanly: No
2. Is it best to upgrade or remove SAV 10 on the server and do a fresh install of SEP ver 11:
SSC and SEPM can be installed on the server. While installing SEPM, you have a choice of importing information from SSC.
So, once you have installed SEPM, deployed all the computers with SEP client, then it will be safe to remove SSC from the server[ it requires a reboot ].
As far as client migration is concerned ,you will need to re-deploy the clients after creating new installation packages from SEPM.
You don't need to uninstall any SAV clients. SEP will overinstall itself on the existing SAV installation.
You can refer to the document below:
How To Migrate From Symantec Antivirus System Center Console To Symantec Endpoint Protection Manager
http://service1.symantec.com/support/ent-security.nsf/854fa02b4f5013678825731a007d06af/eda2ac3faa9a31b0882574f90001484e?OpenDocument
Here is a Flash Demo of various activities involved with respect to Symantec Endpoint Protection:
http://eval.symantec.com/flashdemos/products/endpoint_protection_install/index.html
Note: You can not install SSC and SEP Client on the server. Hence if you are planning to migrate all your clients to SEP, your SSC Server will be the last client to be migrated.
Cheers,
Aniket Amdekar