The hole has been there since about 10 am yesterday morning. Were you able to see the picture after all? I wish I could attach the picture, but I'm not allowed yet. I can see it's little head, beak, and part of the chest. I'm afraid to pull off any more, do you think I should, or just leave it alone for a while?
If it's been that long, he is probably getting tired. I would start to peel back the shell around the opening very gently.
I upload pics by first uploading them to my profile, then selecting the little picture symbol in the box you type in to make them load on my post.

Make sure to keep the outer membrane moistened when peeling off the shell. There is an outer and inner membrane. The outer membrane is attached to the shell, the inner membrane surrounds the chick.