hears some pictures that may come in handy for any one looking to check or change haldex or diff oil levels on a gen 2 diff as fitted to audi TT S3 and mk5 R32 and the haldex filter is behind this plug will edit this to add more info once iv looked it up
the Haldex oil is G 055175A2 and the haldex filter is 02D598574 the final drive oil is G 052145S2 for 1 ltr and G 052145A1 for 0.5 ltr