There is no option that you can configure to determine where Glimpse will render its script tags, the script tags will, like you mentioned, be rendered right before the </body>
tag, this to minimize the impact of the Glimpse client while loading the rest of the page. This injection is also done, independently of you using ASP.NET MVC or ASP.NET WebForms for instance.
On the other hand, the issue you are mentioning is already known on the Glimpse issue tracker and is being worked on, so don't hesitate to give additional feedback over there.