OK, clutching at straws now...
Are we assuming the ECU is OK, or has that been independently checked? Maybe worth trying it on a working system?

Just to recap - the fuel pump runs when the engine is turning, and the injectors are firing.. so the crank sensor is OK..

**STU - on L6 is the phase sensor signal also required to be OK to be getting injector signals??**

Both ECU pins 1 and 19 got good ground connection?
Presumably pin 20 has 12V supply or nothing would work...

just kinda thinking aloud here...