From the SSC - Right-click your Primary -> All Tasks -> Reporting Configuration -> Configure Reporting Server
Put in
http://<Server IP>:8014/Reporting 8014 is the default port so if you changed it then you need to change it here. Depending on how you have things setup, this setting should propogate to you secondary servers.
If you have reporting agents installed you can do it a different way. Also if you have AMS admin Utility installed, you can use it but the above is the fastest and simplest.
The issue I think you are going to have is that 70,000 clients is alot to ask of your sepm. It does put an extra load on your SEPM. Also if you plan on going to 11.0.6a, we had an issue with SAV10 clients reporting to the SEPM and had to stop it. It seems the latest version does not handle SAV10 reporting very well.