Add product labels to open ends of conveyors

Add product labels to the open ends of conveyors, when connected to storage buildings/factories. I've found myself connecting belts incorrectly, and products heading to incorrect areas.

Could we go one step further, and show that information in the transport's building menu?
Similar to how the building menu shows the current contents, but based on a prognosis?
Of course, that would only work where there CAN be done such a prognosis (e.g. not connected to a storage without any assigned product or similar cases)