Cheers Nev,
I'm fairly sure that a new Alternator will fix it, but it's just the buy an Alternator, buy a wiring loom, buy a fuse/relay box, buy something else, etc, etc, pathway, that I don't want to go down.
I put a few feelers out to folk who know more than me, but I can see an Alternator on order by the end of the weekend .