WebMethods revert back procedure to the older version(8.0) after WM82 upgradation


Before doing the migration I want to ensure the version revert back procedure.
Could you any tell me the procedure?

I found following information from the document 8-2_Upgrading_webMethods_Products
We can not be able to roll back to previous releases. Only be able to restore previous releases from the backups.

What is the procedure to do this backup restore?

--> Is replacing the backup IS instance folder with the 8.2 instace folder is enough?
--> Or have to follow any other procedure?

Thanks in advance