Castrol V8 gearbox oil showing 'MANUAL' and a picture of a gear lever on the front ...
... and 'MANUAL' and 'GL4' on the back.
Castrol rear axle (and steering rack) oil for all MGBs showing 'DIFFERENTIAL' and a picture of an axle on the front ...
... and 'DIFFERENTIAL' and 'GL5' on the back.
