well it just so happens that the 8 colours are the exact same 8 colours used for 1-8 in the resistor colour code used in electronics.
Brown = 1
Red = 2
orange = 3
yellow = 4
green = 5
blue = 6
violet = 7
gray = 8
now i can remember what thing is plugged in to which a16 input or output without any stickers or other marking. just by looking at the color of the cables coming out.
sorry it wont work for all you fancy people with all your gear in enclosed racks
most of the things i have are "desktop" anyways (which is a huge pain when it comes to making space for them)