The full install of Panther (3.5gig) is bigger than my entire HD (3.2gig) !
3. Verify that you have enough hard drive space.
The amount of free disk space required depends on your computer and the way you choose to install Mac OS X. You should have at least 2.0 GB of available space on your hard drive to install Panther. You'll need a minimum of 3.5GB of available disk space if you install Panther's optional developer tools.