Could someone tell me if a 17 year old with a GED work night shift?

According to my (slightly out of date) source on child labor laws, in KY there is no restriction on a 17 year old's hours when school is not in session. Since a 17 year old with a GED, or one who has already graduated, is not subject to school hours, it would seem to me to stand to reason that they would be able to work any hours the employer wants/parent will permit. However, I would strongly suggest confirming that with your school district before putting it into practice. I can't guarantee that the laws have not changed since the publication of my source material.

It appears that the hours of work restrictions for a 17-year old only apply if the individual is attending school.
http://labor.ky.gov/esat/childlab.htm