Here's a video: https://www.youtube.com/watch?v=j6m7r6biQBw
Pull the timeline to about 3:40 to see where Diggy starts to tackle the stones.
He starts by pushing the first stone on the left UP. That is little counter-intuitive.
Try to get to these key stages.
The person that made above recording set up the stones for 2 first, but before clearing she/he backtracked and did 3 first. Makes more sense to me do 2 and clear, then 3 and clear.
