I would have guessed that any USB 2 to IDE drive adaptor cable would suffice.
That could be worth a shot, as I do have that adapter from a more elderly Newer Technology device.
The sloth in me wonders about the next part….can I do this without removing the drive? i.e. power the drive by turning the G4 on. It looks like I could reach the connector, which loops from the optical drive and is in a space between the drive and a fan housing.
Stay tuned, everyone.