O2 Sensor Replacement '87 5000S Quattro

["Kusik, Todd" <tkusik@visa.com>]

Hi all,

I have a '87 5000S Quattro with the 2.3L NON-turbo engine.  I want to
replace my O2 sensor, but can't quite locate it.  My suspicion is that it is
under the intake manifold (which is where most of the exhaust manifold is).
I have the Bentley 'Factory' service manual (what a joke), but it doesn't
have a picture for this engine.  Anyway has anyone done this on theirs and
have the location or any other pointers.  

TIA 

Todd ('87 5000S Quattro  214,000 miles still going strong)