Ok, so 8.5js are on the back, that is not the issue.
Looking at where there has been contact, my initial description of so where between rubbing and grinding becomes clearer.
It appears that the highest point of the inner edge of the alloy has been making contact with the outer housing of the suspension (pics to follow).
Off side, this had worn away the black paint on the housing, and it is down to the metal. Near side is better, but still shows signs of the same.
The off side also shows a small amount of dirt having been cleaned off the inner front edge of the wheel arch.
The ONLY thing that makes sense to me is that somehow, and I genuinely do not know how, the front wheels were not fitted fully flush with the hub, meaning that when I went round a corner to the right, a small amount of play in the wheel caused it to rub. I will have turned to the left less often which is why the near side was less affected.
Does anyone else have any other theories?
Jimi