Same problem here...my small pond has (I'm guessing) 30 or so CC's, all in the 6-12 lb range. What I really want is ALL of them out of there, but they're almost uncatchable.
I'm seriously considering draining it and starting over. I've got all sorts of ideas of what to do with that pond (SMB + YP is the current plan) but all of them would have a serious flaw with that many large alpha predators already stocked.
Could you trap them? Bait a trap with dead trash fish? I've had some success trapping bullheads, but no experience with CC.