Another thought, rather than needlessly change diff and gearbox oils at such a low mileage, I would turn attention to changing hydraulic fluid in the brakes and clutch as being hygroscopic, it can cause corrosion, particularly in the rear slave cylinders. Recommended to be done every two years.
Also bear in mind, that the tyres are now about 8 years old and despite a good tread depth should be considered for renewal due to hardening of the compound. (Some even go for a 6 yearly renewal!) up to you, but I wouldn’t want to stretch it much longer than 8.
