Just so you know, the crop is not centered on a chick or an adult, but it's especially obvious on a chick. The crop hangs to the right of the bird's trachea/neck.
This photo is of a parrot, but because the bird is naked, it clearly demonstrates the location of the crop. It is not centered, and on a chick it will bulge out to the side quite a bit! Sometimes it will be so full that the skin shows between feathers/fluff. This is not in of itself a cause for concern.
http://www.birdtricks.com/blog/wp-content/uploads/2012/03/IMAG0650.jpg
This thread has photos of a chick with a very full, but normal, crop. The danger is of course if it will not pass naturally. The best time to check is in the morning before they've eaten.. if it's still huge it may be impacted.
https://www.backyardchickens.com/t/...y-chicks-chest-but-i-thinks-its-just-her-crop