had no problems what so ever fitting mine and was a perfect fit.(not to sure about this but you say you started from the out side and worked inwards) was told by mike rainbird this is not the way to fit them and the centre of the splitter should be fitted first and you have to work outwards. hope you get it all soreted as im sure they are all made from the same mould and all pre drilled holes will be done to some sort of template.