For Dan K. or anyone else with the required expertise:
Can an optical drive from an iBook G4 be installed in a 400MHz Powerbook G4?
Specifically, the pix I've seen of TiBook G4 optical drives show them to have a different form factor than more modern optical drives like those in the iBook G4. But I don't know if the drive is a different size/shape, or if the TiBook just uses a cage/carrier that makes it look different.
I also note from Dan's Web page that iBook G4s use, among other models, a Matshita CW-8123 "combo" drive, whereas 400/500MHz TiBooks use, among others, a Matshita CW-8121-B. I imagine - but do not know for sure - that these drives must share a basic form-factor, in which case the two different models of Mac would have physically interchangeable optical drives.
Can anyone confirm?