Setting default version of Excel to open XLSX

I recently upgraded to MS Office 2016, while retaining my older Office 2011 on my Mac as well. I have a late 2012 (27") iMac running El Capitan v10.11.3.

As many users of the MS Office for Mac Community Forum (on the MS website) can attest, the newest version of Excel has a few performance issues as well as missing (deleted) functionality. By default, any Excel spreadsheet I now try to open, opens with Excel v2016. I would like to have Excel v2011 be my default application while retaining v2016 on my Mac for testing purposes.

I realize, of course, I can have an ALIAS of Excel 2011 on my Dock, and drag my file to that Excel icon to force it to open with v2011. But still, I would prefer to just double-click on the file and have it open in my preferred version of Excel

I know how to change the default app for a file type (such as associating .TXT with BBEdit instead of TextEdit) by

1. selecting a file
2. choosing Get Info
3. going to Open with: and selecting the appropriate application
4. then clicking on Change All...

But this does NOT work when trying to change from one version of Excel to a different version of the same application. Any thoughts? Thank you.