Whilst the tank was off, I hard wired into the rear light supply and earth - works a treat and leaves me the dash connector for something else should I need it.

Also took apart the regulator/rectifier connector and it was swimming having very lightly washed the bike. Considering the position of this connector, there is no protection from the elements and I'm not surprised some have failed. Dried out and with plenty of WD 40 a balloon was used to sleeve the join.. Will check it all again after a soaking.