Ugh... that level. Yeah, that one took me a while. I don't remember the exact positions of things right now without going back and replaying it, but the basic setup is that you need to position an orange block such that the first big guy you move can be "broken" by a white-on-orange in a position where its legs are blocking your ability to move a big guy into the stuck orange space (I believe the position you want is to place an orange block three spaces above the blocked orange block).
You then use the spare orange blocks to clear out only enough of the water to let you move the second big guy's arm into that space. If you positioned things right, , a leftover water block should remove one orange block when you do that, letting you free up the two blocks remaining from the second big guy so that you can move all the free blocks into position.