I have a Seagate Momentus 5400.3 160GB:

* Model: ST9160821AS
* PN: 9S1134-042
* FW: 3.CAE

I want to replace the PCB on the drive but I can't find any PCB's or drives with the exact PN and FW numbers. Do these matter or is the only requirement the model number? I don't mind buying the same drive and removing the PCB either, I'm doing this more to play around so I don't really care if it works or not but I want to make sure I'm doing it right.