In the admin section is it possible to display a ForeignKeys element in another field. What I would like to do is select a restaurant via its ForeignKey. That restaurants location will then be displayed in another field. Probably a CharField.
Yes, this can be done with some JavaScript added to that admin page. The script would trigger on the drop-down being changed, make an AJAX call to a view on the server to retrieve the location, and then update the field in the admin form.