We'll create fresh WordPress site with Custom Script Integration installed. You have 20 minutes to test the plugin after that site we'll be deleted.
This plugin provides custom meta boxes in default Pages and Posts of wordpress where you can enter any scripts for each respective pages or posts, for example:
You will get a meta box under each of page and post. The Meta box will have 4 Text Boxes, in each section you can add codes for:
Plugin Documentation:
http://www.wpwox.com/wp-plugin/custom-script-integration/