在.net图表图例中仅显示添加的自定义项目

I have a lot of charts i am graphing and for some i need to give each X value a custom color and have that item in the legend as well. The following code achieves this but on the legend there is always the first default value which is now pointless. How would i remove/hide/clear that original default legend item? Just for reference the chartColors array is just an array of colors to cycle through. I have a lot of charts i am graphing and for so