Family Treemaker Question

So I have discovered that one line is wrong.  It goes back from my ggg grandfather's parents, about 4 more generations on one side. 

Is there a way I can disconnect that whole line from my ggg grandfather's parents on back, without deleting them completely (just leaving them as sort of a lone branch by itself) until I feel comfortable completely getting rid of them?  I want them disconnected from him because I want to add the correct line, but I have a feeling that wrong line may fall in somewhere with a sibling or something, so I want to keep that little 4 generation branch available to me, just in case.

I use Family Treemaker, but do not have my tree on Ancestry.

thanks