The A4000T disks are different to other OS3.1 disks.
One difference is that they contain 'workbench.library', although, I think there are other differences.
My A4000T disks are corrupt, and so I wouldn't mind an unmodified original backup (if that makes sense :lol: )
--Edit:
In fact, the non-A4000T disks won't even boot properly on an A4000T