Casey, I wondered how you did it initially, but with the photos, everything is clear, haha. I'm facing the same problem as yours, so lazy to take out all the pots in the tray when I did water change, especially when you have many of them. Hmm... your method is helpful since I'm using the same kind of tray. Thanks.
JK's method is what I am using for some of my CPs too, sphagnum moss can be grown easily with this method.