The method could change depending on license level as logic editing only exists in higher level licenses.
So, as far as I know, if you don't have the logic edit license you will need to:
1) Export the netlist (file menu)
2) Export the libraries (file menu). (Make sure your pad and symbol path points to the path where you exported these)
3) Hand edit the netlist from step (1). Fairly obvious netlist format
4) Import the changed netlist
Hope that helps!