I would concur with essentially all of your comments here. Sourcing the
intake manifold would be a serious help, as would the rubber connector to the
AFM. Otherwise everything else is available from the Diesel engine and the
donor vehicle. If a non-diesel trans is used, the bellhousing and input shaft
would also be needed.

The lack of an O2 sensor with appropriate ECU support would require the
complete replacement of the kit-supplied motronic unit with a full component
set from a donor car (probably approaches the cost of the engine in a
recycling yard). This would include the ECU, timing module, sensors, AFM,
idle control equivalent and harness (if the connector is not identical).
About $500 to 700 for the 2.0L late model Motronic hardware in SoCal. The
possibility of adding in an O2 sensor to the SA unit leaves me incredulous.
The ECU maps or programmed software are burned into the EPROM. Can't imagine
the multifunctional software being imbedded to remap the timing and fuel
curves to utilize a not-previously-supported O2 sensor and full Lambda loop.
The only possible thing I could visualize would be jumper selection of the O2
sensor option internally and an EPROM replacement if the Motronics board
supports a removable chip.

Just an opinion.

Frank Grunthaner