Making a bottle cap look closed
Hi,
I'm trying to retouch this image so that the cap on this bottle looks more closed (decrease the size of the opening). I've tried both cutting the cap out of the image, pasting it on its own layer and bringing it down closer to the bottle neck as well as widening the black in the opening closer to the edge of the bottle edges.
Neither looks quite right.
How could I do this so that it looks natural but still appealing?
Thanks! 
