I'm trying to increase my understanding of CC's Mazda 5-speed:
I take it that Section A is Mazda and Section B is Caterham? In which case, presumably the Mazda version would have a one-piece bellhousing that attaches to "A", whereas CC has developed its own "B" so that the same gearbox could be used with different CC-designed bellhousings to suit different engines?
Also, I take it that the hex bolt (purple arrow) is the one that must not be touched for fear of messing up the internals? If so, what does it actually do?