Thanks for the help guys! I think I may have a Discovery diff assembly but with a defender 4bolt flange fitted! The seal looks like FTC5258 which is for the Discovery! Just wondering did Landrover have a kind of cross over period where they may have used the same diffs in both Defenders and Discoveries or do you think mine may have been swapped at some point!?! Ill try taking pictures when I come to do it! Had to put it all back together without new seal because I had the wrong ones!