You can't have two different versions of Office installed on a Mac. Whichever deployment method you decide to use, the following information can help you plan your Office for Mac deployment.
Additional deployment information for Office for Mac Even though you can't customize app bundles, you can configure preferences for each app. This change prevents Excel from starting. For example, even if you don't need the French language resource files for Excel, don't delete them. Don't add, change, or remove files in an app bundle. This means that you can't customize the app bundle before or after you deploy Office. To help improve security, Office for Mac implements Apple app sandboxing guidelines.