A few questions, friend has access to a Leo with the 456 software and ISO cable.
1. In and around the fusebox area there are a number of connectors with apparently no home to go to.
a) Can anyone help identify them.
b) Is (6) the test for the rear spoiler ?
2. Engine ECU's and their ISO cables
Where are these hiding ?
The engine ecu ALDL connectors (x2) are behind the kick panels, on the right and left (interior) sides of the car. You can also connect to them through the OBD-II connector if the 456 is 1996, or newer.
I am not aware of any self-test that can be done to the rear spoiler with an SD tool.
There is limited info in the WSMs identifying the dongles you highlight. One dongle is labeled "Diagnostic." I recall that being for the brake system. If you have access to the factory "diagnostic Sheets" they may be helpful in identifying the ALDL connectors by the wire colors.
If all else fails, connecting to the incorrect connector will simply result in a communications error, with no damage done.