Buzzing out the harness using the correct wiring schematic for DME 7.8 showed that the harness to be in good shape. To buzz out the harness disconnect all connectors on the ECU.
Use an extension wire to the multimeter to check the resistance between the wire of interest in the harness and all of the pins going into the ECU and to the car body. This will find a broken wire, or a short between two wires or a short to ground. I use a sewing pin to reach into all of the connector pin holes to check for continuity.
Everything checked out, so other than the bad relay there was nothing wrong with the SAI found.
The car is back together, and I even painted the rear bumperettes during the down time. I used sandable primer, sanded to get rid of the texture on the bumperettes, 3 or 4 coats of duplicolor general purpose black, 2 or 3 coats of clear. let dry several days then sand to remove remaining imperfections with 2000 grit paper and finish with polishing compound.
With any luck , this is the end of this string.