If you had CS6 perpetual and have install Creative cloud versions of Photoshop. Uninstall CS6 then install CS6 via the creative cloud desktop application.
If you only have perpetual CS6 I would suggest that you try installing CS6 on top of your current CS6. That should back level CS6 to version 13.0. After you install CS6 use menu Help>Updates. That should update CS6 to version 13.0.1.3 Windows or 13.0.6 Mac and ACR to ACR 9.1.1 CS6 should be activated and your Plug-ins, Preferences presets and actions will still be installed.