I can't put up the sign on the wharf for Paul Revere to show way to ship

Area is sparkly on the boxes, hint says I need to hang the sign, a little hand grabs at the boxes but I can not hang the sign It is completed and waiting to be hung. Where do I hang the sign?

I figured it out. I had to go back 2 clicks and the sign goes above the shed door I had to bust through earlier. The sparkly area at the boxes was then something for me to pick up.