I am trying to apply a custom format to a grid line in a bar chart to highlight one specific grid line. Let's say the value axis range is 0 to 10 with 10 grid lines. How can I increase the width and change the color of the grid line for the value "2". Alternatively, one could also put an line object over the grid line. This would require to coordinates of the grid line. Is it possible to obtain the locations of the grid lines or axis ticks in a bar chart?
I tried to look at the attributes of the bar chart value axis using the dir function, but was not able to obtain the necessary information.