RS2 6 speed

[MarkUSA]

Greetings from across the pond.
I am a fluid change away from finishing the install of a RS2 6 speed into my US spec 1999.5 A4 1.8t quattro but am confused by the drain/filler arrangement.
I note there is a drain plug on both the front differential case and the rear gear case. I can find a filler only on the front differential case (3 o'clock on the driver's side final drive cover), however. Is there only the single filler plug? Do the two cases share gear oil or is there a filler I'm not seeing for the rear gear case?
Thank you in advance.

[MarkUSA]

Never mind. I located a copy of the CRB/CGR manual at Erwin and can see that it is a common oil fill source. The rear drain looks to be provided because of a high spot between the two 'halves'.