Cisco Pix 501 Factory Defaults—Completely starting over….

How do you get the Pix 501 to factory default and reboot to the wizard? I want it to completely remove ALL settings and start over from the very beginning. The command “config factory-default” does not do anything but erase some parameters. This is not what I want. I also tried the restore defaults in the PDM and they do not do what I want either. Do I have to re-image the pix to do this? Any help would really be appreciated.

Thanks in advance….