Gearbox/clutch

[Willie]

I would imagine that the improved oil seal is on the lines
of the MGB five main bearing type( the early MGB's had a
3 bearing crank with exactly the same Archimedes screw
rear oil seal as on the Minor). The later type is a very
large diameter rubber ring very similar to the hub oil seals
and, although my memory is not good on this, I know that I
fitted a new one without removing the sump so access was
gained by removing the flywheel.