I have that same receiver and I have not even considered trying this. I suppose I could but I already have Atmos speakers atop my Klipsch towers in both the front and rear in a 9.2 setup. I will look into it and if I can figure out a way, I shall return to this question with my answer. In the meantime, I suggest you did what I did prior to purchasing official Atmos speakers.
Try putting a small bookshelf atop your front and rear L/R units. I had a couple of spare pairs and did just that while I waited and saved for the Atmos units. Let us know how it goes!