Selectable production line icon

[pedter]

I would like the option to be able to manually set the icon of each production line rather than the icon being automatically chosen for me based on the first recipe. Without the option my different rocket part production lines for each planet look like this:

From this screenshot no one can tell which production line matches which planet.

However, I have been unable to find a way to change the icon within the mod. It would be significantly easier to tell which production line matches each role if I could manually set the icons to correspond more closely to their purpose, like this:

With this example it is much easier to identify which production line matches which planet.