Well got a new brush/ regulator unit and it still didn't fix the problem although the alternator is now kicking out over 14v instead of the 13.7 or so it was doing before. The battery has started to die overnight and I've ckecked to parasitic drain which isn't huge so it looks like the battery has bought the farm.
Some of the other jobs to do:
Wing mirror adjusters need nuts.
Oil and filter change
Small coolant leak somewhere probably to be expected given I froze the engine last year.
Getting a bit sick of the backbox, stainless steel universal type way to loud. The centre pipe was welded at the last MOT so I suspect that will probably give way shortly.
Speedo is bouncing around - new cable time.
Sort out the shocking job i've made of the paintwork.