Davebic - Another warm welcome to the forum!
I want to commend you on your first post - it's a great topic and one the forum needs to discuss. I was just about to post this question myself as I'm considering STOCKING GC for the first time and want to remove them in about 5 years before they become ultra large, less efficient at veg control, become pellet hogs and muddy the pond. I hope experienced guys keep offering their ideas as we all need to have a firm grasp on how to remove them eventually.
When time allows, open another post and tell us more about your pond, your goals, and how you found us!