I have finished replacing all the linings on this bass now .
The back linings are 22mm wide and 2.5 thick and the top linings are really small at 10mm x 2.5 . Its my bass so I'm prepared to experiment with the small top linings.
The last linings were up to 10mm THICK on the c bouts and about 32mm wide all round.
I've read so many contrasting viewpoints on the difference that smaller linings can make ...
Im not expecting a miracle though
In the pic you can see the 'clean' wood where the old linings were.