PowerBook G4 550Mhz case change?

Hello,I have a doubt and I'll be gratefull if you help me with this:

I have Powerbook G4 550Mhz Titanium and PowerBook G4 400Mhz Titanium...

My question is:Can I use the case from this 400Mhz to put all the parts from this 550Mhz into this one because this 400Mhz's case is better preserved...??

are the cases for both models same and perfectly suitable one to another?

is there any guide to completely take apart both of these models??

It will be very helpful for me because I would like to switch cases between these two models....

I'm awaiting your reply!

Best regards,

Stefan