I had to replace no5 as the original was rusted and leaking. This was done by Austin Garages at the same time as the diff and gearbox oil change.
I noticed that the position of the centre and rear exhaust sections where they are clamped together were off-set. That when not joined together the centre pipe was putting no weight on the central exhaust hangers ….. it was being supported from the engine manifold. When clamped together the rubber centre exhaust hangers were still very slack. It makes me want to check whether the exhaust system as a whole is hanging correctly.
Perhaps if a couple of flexible sections were added to remove the tension in the system? …… another project!