I'm not sure I can really say this is an annual service as I check the car regularly during the year anyway. e.g. before going on holiday I check all the key nuts and bolts, the tyres and oil are checked etc. None the less, the Christmas period has become the oil change, longer than normal bolt tinker and general review / tidy of the car.
This year I downloaded the excellent Duratec service schedule which was put together by Marcus and Shaun and available from the Lotus Seven lub Blatchat area. I think I will add the bolt tourque settings to the spreadsheet so I only have one document to review when I next service the car.
I put Fuchs Titan Race Pro S 5w30 in the car again with a Mahle OC11 oil filter. Neither the gearbox or the diff needed any oil. Happy Days.