Like Michael H says, bolt on a HD unit and end your rectifier problems. HD p/n 74540-01, easy and cheaper. AMC as for, "looking at how I can prevent the new one (£300- ouch!!) going the way of the first", I suggest you put it on the shelf in your garage. The problem is not that the CE unit is exposed to the elements, it is that it is, "delicate", or a POS. Buy an HD one for $50 on ebay and keep the CE one in the garage collecting dust, it's good for that.
