Hi Water Lover, yes you are right! No.766 (stack 22,21) was taken from the playground slide. I have to tip toe & stretched both my arms all the way and kept snapping in order to capture the best shot!
For No.766 (stack 25) & No 768, there were taken from 15th floor of Blk 725. This is the only level that can captured these stacks. Again, due to the design of this block, i have to stretch my arm fully and keep snapping away.
For the rest, there are a lot more easier, just take from 10th floor of Blk 723 without the need of any stretching "exercise".