I had a similar issue with mine, 40amp denso blowing circuits, some working then not, loads of silly stuff. Took the alternator to a local specialist who replaced the regulator and voila all happy again. Not suggesting that this is the cause but if you have a local alternator specialist then take it there first. If not, then it’s a bit of a trek but MC alternators in Warrington will help you out.
Cheers, Craig