Do mushrooms and scalpels mix?

Does anyone have any tips on how to transfer a mushroom from LR to a plug?  I tried 1 to see if it could be done, but fairly well butchered it cause the rock was so irregular and hard to cut around.  It turned into goop a few days later and I had to siphon it out.  Probably should have asked around before the attempt  .
The current rock they are on is way to big for the new rockscaping plan I have and I want to frag all the little ones, and put my biggest on a different, smaller, rock.

 

Thanks for the advice. Ever heard of blowing a powerhead at it and putting a frag in the way when it starts migrating? These things are so mobile I could probably let it move itself to a plug in 3 days