I think what you're looking for to install debian onto an old world without MacOS is quick or miboot.
I hear they are real buggers to install and one of them can screw your system up rendering even your mother board useless. Thus this is why a lot of people opt to install MacOS. I know that classic installs can be realy small, less than 5 gig while OS X has a min of 5 (something like that). If I remember clasic can install onto 1. Not to say anything about debian but here are a few links http://www.ubuntulinux.org/search?SearchableText=miboot " Quik is an Open Firmware-based bootloader for Old World Macintosh with Open Firmware version < 3.0, CHRP, and Apple Network Servers. It's similar (in purpose and concept) to yaboot, which is used on CHRP and New World Macintosh with Open Firmware version >= 3.0. It does not run from Mac OS, and does not require Mac OS or an HFS partition to exist on your hard drive. Because it's very dependent on Open Firmware, and because the Open Firmware on Old World Macintosh is very buggy and difficult to work with, much of the information on this page describes how to work around firmware problems."http://penguinppc.org/bootloaders/quik/ -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]