Mike-WSM.
That diagram implies that there is an alternator on this engine. I stupidly discounted that, assuming that the mags would also handle DC charging/supply.
So apart from my droning on about the mag AD et al, what rpm does this alternator start charging at? My Series III Land Rover is a bit dodgy and it needs about 4,000rpm to kick in. And because it's not A1 condition, I'd bet that its' output is more than a little noisy.