After looking at the Google Help Topic on adding Conversion code. You will want to first decide what page is has the action that you are looking to have customers complete on your site (for example if the goal is to get customers to call you then you would want to add this code on your contact page or if you are just wanting to keep track of people viewing your products then this code would go on your products page).
To add the code to your site, you will want to add an HTML widget to the corresponding page in SiteBuilder.
Here is how you can add a widget or HTML code to your website:
1. Click Websites Manager in the left navigation menu. Then, click Edit Site.
2. Click Insert in the top toolbar. Select More from the drop-down menu. Then, select HTML.
The HTML placeholder will automatically go to the upper left corner of your page. Click and drag the element to where you want it on your page. In the case of tracking code, you can usually place this anywhere on the page (some tracking codes may ask you place the code at the bottom of the page)
3. Then, click Enter or Paste HTML button in the HTML settings on the right.
Remove the current text in the small window and copy in the html code you have for your widget.
4.Save and Publish your website to see your HTML widget on your website.
Important: You need to use preview mode or publish your site to view your HTML code or widget. You can't see HTML elements in edit mode.