Regin,
I'm guessing I will have to take the lug down a bit more to the 43mm. Although if you download the current build manual (the one I had when I did the diff mod)it says to take the centre of the backplate down to 43mm and theres no mention or sight of the lug. But on the build manual that came with the kit (which is a older version) says nothing about taking the centre down but it does say the lug must be taken down to 43mm and shows a picture of it. I think the best thing is to strap the backplate to the mill and take everything down to 43mm.
thanks
Jason
Currently, I am qualified to plead ignorance.