Automatic sign for chest

We need a sign witch automatic shows us the first item of a chest by placing it on to. We need to click trough the sign to open the chest - so the sign won't be in our way opening. The think behind is the copper golem. If we build an automatic sorting system an the golems start filling empty boxes u need to open any box to see what they sorted in. By a touch trough sign u can build a full system without the need to change signs over and over again. May it cost like a frame with redstone and only works on redstone chest - still would be good.