I need help. Moving a large toadstool leather

[copenhagen_cowboy@live.co]

I am upgrading to a larger tank and need to remove some of my corals off of my live rock. I have a large toadstool leather that the base stem has attached itself to half a dozen rocks before coming to the large top. The base is about 1.5" - 2" in diameter. How can I remove it without killing it. If i start removing rocks it will just rip chunks out of the side of it. Im scared if i cut the base straight across it will be to much damage and i can't get all the rocks out and support them enough to chisel around it. I look forward to your suggestion and if you have had any luck personally doing something like this.