[PyMOL] Breaking down PDB files

[Tony G. <to...@ca...>]

Hey everyone,
    I know I should be past this, but I can't seem to figure out how to do
this.  I have a couple of crystal structures that contain multiple copies in
the asymmetric unit, and I would like to superimpose each copy to see what
the differences are.  One way is to break the PDB file into one file for
each chain, but I'm wondering if there's a better way to handle this in
PyMol?  One file (1CX8) has 8 copies and the other (1DE4) had three.  I
tried split_states but it didn't work.  I also tried aligning say chain A
onto chain B directly but that failed too (as expected).  Is there a
straightforward way to do this or do I begin splitting these 700 residues
proteins up by hand.  I wouldn't ask except it's a recurring problem with
many of the structures we study so I'm wondering if a general solution or
script exists or can be made to deal with this.
        Tony