I don't know why I brought up an iMac G3.... :

Anyways, if your Beige G3 tower has the Apple Ultra Wide SCSI PCI card, then you need to apply this firmware upgrade:

http://docs.info.apple.com/article.html?artnum=25176

I think for Panther you might have to use XPostFacto. Plus, the partition on your hard drive needs to be smaller than 7.4 GB when installing OS X, otherwise it will not work.

http://www.lowendmac.com/ppc/beige-power-mac-g3-1998.html