What is the width of the Sierra diff assembly. From bearing hub face to bearing hub face?

Or can I try and explan it like this....
If I would make my own De Dion axle, what must the distance be detween the faces that the bearing carriers would be bolted to?

Is there a difference between the rear hubs with disk brake lugs and those for drum brakes?

This has been covered before and as luck would have it i've just been reading the articles.

(not relevent to you, but if someone searches)
Escort / Capri / Cortina axles
http://www.locostbuilders.co.uk/viewthread.php?tid=23812

Sierra axles and a mention of De-dion
http://www.locostbuilders.co.uk/viewthread.php?tid=23755