Using Audi 4wd transaxles

I recently acquired a 4wd Audi trans. I dont know exactly what model it is but it has the id of US on the bellhousing. It was supposed to be out of a mid 80s 4000. Does anyone have any info on this box and how do I determine what series it is (016, 093 etc)? What are the concerns in trying to use the 4wd box other than it is longer?
are you trying to make if 4wd or 2 wd .... i think you have to lock up the transfer part to use it 2wd ... when i use subru trans i have to lock up part it the trans to make then 2wd
You can use it by doing one of two things. You can weld the shafts together just under the rear cover so the forward running pinion shaft has to turn, OR make a special collar to replace the existing to achieve the same outcome.
Hi Wment , You may find the 4wd is two long to fit in a Diablo body, i measured my 016 2wd against the 4wd tonight and the 4wd is 190mm longer than the 2wd.The total length is 848 mm from front of bell housing to rear of the rear flange
The 4wd box has a vacumm operated lock at the extreme rear just in front of the rear flange, it just moves a slip ring to lock the centre diff, and so sends all drive to the pinion down the centre of the hollow tube. I had a look at the code on my box and it starts with US also i pulled it from a 1995 Audi 4wd coupe

The trans would be going in a different mid engined kit car than the Lambo and I think I can handle the added length. I was more interested in the strength and gearing aspects. I cant find the ID (US) in any of the Audi manuals I have. Do you have any specs on this trans?