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As an Admin you can create HTML based ads directly from your AdminCP by creating a new block, select Add Block a choosing HTML Code as the block type.
Place the Google Analytic HTML code in the code input area for the new block and set the location (where on the page you want it) and choose Controller (which page should it show on). For our screenshot below Google Analytics code is added. We chose Sitewide as the controller as we want it all over the site.
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