I'll get out Monday in order to check the height that i raised the car to achieve a level gearbox. While i think on, I'm on 15" wire wheels shod with 65 profile tyres which of course will affect results slightly with differing wheel sizes and tyre profiles.
As an aside i spoke to AK Motors in Rowlands Gill, MX 5 Specialists who did say that the engine was canted 10 degrees clockwise (viewed from the drivers seat) making the gearbox level, unfortunatly we didn't specify the mx 5 model / year.