Final update (hopefully)
Finished wrapping everything, got the airbox & fuel tank on, with bated breath everything lit up and I pressed the starter... Nothing! Just a click click click followed by an F1 C12 error (crankshaft position sensor). This error cleared when switching off the ignition but reappeared after a few attempts on the starter button.
Plenty of cursing, checking the sensor connector, partially corroded and treated. Checked the battery and ensured that was fully charged and not dropping voltage. Then I remembered that when I checked the ground on the starter motor that the bolt moved in and out slightly, I wondered if it might be fouling the brushes and preventing it from spinning. Took it apart again & then tightened up properly, fired up with barely a stutter!
Now I just need to put all the fairing back on etc, I have also ordered some new screen well nut bolts which arrive in a day or two. Can't wait to finally go for a ride again!