You can use the following to move your sharepoint location on your existing TFS Sharepoint sites or Repritng Services to another port or to another server.   Note that you must have the Sharepoint site or Reporting Services already configured.

TFS 2005/2008: During Setup

1. Copy msiproperty.ini from the install media from AT or ATDT folder to a folder of your choice i.e. C:\temp\msiproperty.ini
2. Change the property: VSTF_WSSSQL_PORT from 80 to another port.
3. Start setup.exe under the subfolder of the sku with a command line: d:\atdt\setup.exe /INIFILE=C:\temp\msiproperty.ini.

TFS 2005: Change ports on same server for Sharepoint
http://blogs.msdn.com/elyasse/archive/2006/02/14/532120.aspx

TFS 2008: Moving Team Project Portals to a Different Server Running SharePoint Products and Technologies
http://msdn2.microsoft.com/en-us/library/bb909655.aspx

TFS 2008: Alreday installed, just change Reporting Services or Sharepoint port
Just run TFSAdminUtil ConfigureConnections.   The details are located: http://msdn2.microsoft.com/en-us/library/bb778396.aspx