I don't know much about G3 like i do G4 and G5. My life with Apple began as a computer tech working at CompUSA back in 2001 - and I bought a G4 350 sawtooth and never even owned a G3. You could try to find the disc set for the ibook g3 and that might have OS 8.6, 8.5 I think won't work due to it being for Motorola 68k processors.