Hi Mark,
I believe that you can use any.
There should be two wires coming from the pvl ignition coil which is the feed from the generator. Some of the coils have a separate earth wire that would go to the frame or chassis as usual.
Some coils I have seen do not have an external earth, this is provided by the mounting point of the coil.
If you put the feed wires the wrong way round the engine fires 180 degrees out of phase, no problem with that! just swap the wires and go again. Usual symptom of this is non starting, and occasional backfire down exhaust!
Hope this helps.
Regards,
Alan