Our customized version of the GA tracking code only works as-is, so if you need to do anything with GA that our version of the tracking code doesn't already do, you won't be able to use our GA code for that; instead, you would need to use whatever standard tracking code GA provides for the purposes you require, and that would be entirely up to you to set up and sort out on your own. If you need to put non-E-junkie GA tracking code in your E-junkie-generated thank-you pages, that would go in your Seller Admin > Account Preferences > Common Thank-you Page HTML field.