You'd just end up with a whole lot of 7.5GB patitions, which is nice...if that's what you want......
What you need to do is format your HD with a 8GB partition (or slightly smaller as others have pointed out) and a partition of whatever's left (about 70GB if you have a 80GB drive). The catch is that the 8GB partition must be the first partition for you to successfully load OSX.
It's been a long while since I've played with OSX on a G3, but one thing I do remember is that I sometimes had to boot into OS9 (with any old OS9 on a disk or CD that you may have) and run xpostfacto again, then reboot into osx. That is: run xpost before installing osx, then boot into OS9 and run it again, and then hopefully everything will be roses
