Unless I am missing something, I haven't heard about different wiring on the ignition between any RC51 SP1 or SP2 or US model or EU.
Checked the diagrams on the service manuals, founded in rc51.info
As you can see, the Yellow wire coming from the ignition pulse generator (pick up sensor) is identical to all and mounts on the same ECU pin.
I assume that Roger is referring to the ECU where he says CDI otherwise he is wrong if he refers to the Converter Box.
The Converter Box is the same to all RC51s and it's harness as well.
You can cross check the pictures above and see that in all 4 different models, the same colored wires go to the Con.Box, at the exact same positions on the connector.
The ECU sure is different on the fuel mapping between SP1 and SP2 but that is on the fuel injectors reference.
Otherwise, when I installed the SP2 ECU with the SP2 throttle bodies on my RC, as a lot of other folks in here have done, I kept my crankshaft pickup sensor, my camshaft pickup sensor and everything else OEM SP1, intact.
And my girl fired right up with no problems whatsoever.