Prior to VIN 14650 all Turbo models were fitted with a shallow sump gearbox. The dipstick tube on these gearboxes sits into the gearbox sump. The later models had a gearbox with a deeper sump. The dipstick on these gearboxes sits into the main gearbox casing just above the sump.
Please check that your car has not been modified to a deep sump gearbox as we do not supply dipsticks with our gearboxes.