DO NOT DELETE "USBD.IRX" AND "USBHDFSD.IRX" FILES !

You can replace it with equivalents, they both will be copied to
"mc0:/SYS-CONF" folder by installer and will be used by the
Free McBoot Loader.

You can put your eXtended modules ("XSIO2MAN", "XMCMAN", "XMCSERV" and
"XPADMAN") in this folder, the installer will use it to provide
compatibilty with SCPH-10000 ps2.