Quattro transmission interchangeably

[blarson at zeiss.com]

 I am planning a mc motor turbo conversion in my 1988 Audi 80 Quattro.
But my transmission has bad syncros, and this transmission would require
a more expensive clutch set up than a 1984 4000 Quattro transmission I
have access to(84,000 miles). The 4000q transmission would use a 5kcstq
flywheel and clutch.  I know there is no Torsen in the 1984 transmission
(which I have heard has close ratio's) and it has a manual locking
system that is cable operated, but will it bolt to the 80 body shell,
and driveshaft?  Is the final drive ratio the same?  Please reply
directly to blarson at zeiss.com.
Brian
St Paul MN
1987 5kcstq 189k miles & pentosin free
1988 80q 182k miles