If you get the professional version of UVMapper, you can delete the parts of the object that you don't want and keep the rest. You can even use the original texture maps for that object. Delete out the parts you don't want, save it as a new file, then go into the .cr2 for the original mesh, change the file pointers to the new mesh, and save the .cr2 under a new name. (You might want to make a thumbnail for it as well.) It's quite easy. PC Only, though.