Hi
AdamRPS13 is spot on for the engine and gearbox, but the diff isn't quite as straightforward. Some of the fairly common 2 way diffs need a 75w-140 synthetic LSD oil, others need an 80w-90 mineral oil and some want something in the middle. To play it safe, I'd probably go for the 75w-140 and the Castrol Syntrax Limited Slip, Gulf Gear LS, Red Line 75w-140 GL5, Fuchs Sintopoid LS, Motul Gear Competition and Millers CRX NT LS are good options.
http://www.opieoils.co.uk/c-674-75w-140-gear-oils.aspx
Cheers
Tim