My flash currently contains -

BNE3825RT02#dir
Directory of flash:/

    1  -rw-    29327868  Mar 23 2006 12:33:16 +10:00  c3825-spservicesk9-mz.124-3c.bin
    2  -rw-        1649  Jan 24 2006 06:06:16 +10:00  sdmconfig-38xx.cfg
    3  -rw-     4052480  Jan 24 2006 06:06:42 +10:00  sdm.tar
    4  -rw-      812032  Jan 24 2006 06:06:58 +10:00  es.tar
    5  -rw-     1007616  Jan 24 2006 06:07:16 +10:00  common.tar
    6  -rw-        1038  Jan 24 2006 06:07:30 +10:00  home.shtml
    7  -rw-      113152  Jan 24 2006 06:07:46 +10:00  home.tar
    8  -rw-      756288  Jan 24 2006 06:08:02 +10:00  256MB.sdf
    9  -rw-        9957  Sep 24 2007 09:05:02 +10:00  20070925.cfg

64016384 bytes total (27914240 bytes free)

I only use CLI (no http or https) so can I delete all of the files excluding the IOS?

I need to do an IOS upgrade for WCCP layer 2 redirection. The current IOS is 29M. I assume the new one will be similar (or larger). Only have 27M free. Just want to gain a bit of space as I would prefer to leave the old IOS on there for a rollback.

Boot variable is:

boot system flash:c3825-spservicesk9-mz.124-3c.bin