DOES ANYONE KNOW IF THE RECTIFIER COLOURS FOR THE 750 PASO ARE ALL THE SAME FOR UK SPEC BIKES AND USA ?
MINES A UK SPEC.

the diagram shows a green wire as well
Careful. Let's put it like this. Usually on vehicle electrics black wires are ground, on some regulators tho (i.e. Electrex) ground is not black but green (see pic above). Let's also differ between regulator wiring and the bikes wiring harness. On your P750 the green/black wire is hot. It's the voltage sensor of the original regulator and is connected to the center fuse.So in principle the green wire is just the same as the black