Print to Yosemite printer from a Panther machine

A couple I know have two computers I'm supporting - one is a iMac which I recently upgraded from Snow Leopard (10.6) to Yosemite (10.10). The printer is attached to this machine. The other computer, unfortunately, is a 450MHz Power Mac G4 (AGP graphics) running the last version of Panther (10.3.9). Surprisingly, the 14-year-old computer still works and is actively being used (primarily for AppleWorks documents, which is another "ugh").

Before the iMac was upgraded, I had done something to it which let the Power Mac see the shared printer. I suspect it had to do with CUPS, but I could be wrong. Ever since the upgrade to Yosemite, the Power Mac has been unable to print, and I can't seem to recreate the old setup.

All that is a very long setup to ask: How do I share a printer from a Mac running Yosemite to one running Panther, so that the latter can print?