well as far as I can see, it wouldnt affect anything. If any weight the weight lays over the axel basically where u have that bolt that holds the knuckle in place
So I figued cutting that much of the knuckle wont have any effect on the integrity. when you look at the knuckle and you but it theres like a little triangle shape support on the top side. dont cut or go passed that triangle and you should be fine