Hi Mike, 

No problem. 

You can also save each chain and heteroatom  in CHIMERA by doing  “select:.a” -> GUI->  Save PDB  and “select:.b”->GUI-> Save PDB

OR

run a simple script below: 

f = open('chainA.pdb','w')
f2= open('chainB.pdb','w')
pdb = open("1c1d.pdb","r")

for line in pdb:
        if line[:4] == 'ATOM' and line[21:22] == "A":
                f.write(line)
        if line[:6] == 'HETATM' and line[21:22] == "A":
                f.write(line)
        if line[:4] =='ATOM' and line[21:22] =="B":
                f2.write(line)
        if line[:6] == 'HETATM' and line[21:22] == "B":
                f2.write(line)
Hope this helps, 
Dave