Swapping WR for 20v engine

[Philip Ross <rossp@blythswood.org.uk>]

I have the opportunity to buy a low mileage 20V turbo engine from
an S2.  The engine has done 20K miles and I think its the 230bhp engine.  
I am thinking of buying it to fit into my 86 WR engined Ur quattro.

I know that this has and can be done but that it may also have several
complications.  Can anyone tell me all that I will need of the S2 and
anything to look out for.

Thanks in advance.

Philip Ross.
Edinburgh.