I don't know what you have tried, but you are supposed to be able
to assign different management clients on a file by file basis
via the include statement.  So the approach would be to set up
a management class with a copy group having the only file delete
period you desire and then assign whatever files you wish to
that management class via the include statement.  The syntax is

include <filespec> <managementclass>

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Robert P. Klein                          KL2 AT CU.NIH DOT GOV
Robert P. Klein                          KL2 AT CU.NIH DOT GOV
Phone: 301-496-7400                      Fax: 301-496-6905
Mail:  DCRT/CFB/ETS, 12A/1033, 12 SOUTH DR MSC 5607,
       BETHESDA, MD 20892-5607
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