Just got a 1999 a4 avant 1.8t sport and have a few q's... Cambelt change interval? Seems to suggest 115k in the owners book which seems a bit crazily long! Retrofitting cruise control? How, and how much (second hand bits obviously)? Centre armrest...was one fitted as an option? (and thus i can see if i can find one second hand) Oil type and viscocity? Gearbox oil type and viscocity?