Mailchimp Html Template Sizing Issue

I have an editable html email template in mail-chimp that I need to submit to an advertiser but it needs to be a max width of 600px with 5px bleed (so images and banners at 595px)

Something is knocking it out of 600px and I can't figure out what it is ...

I have not finished the content yet but Ideally would like the issue fixed so that I can complete the rest of it in the right format.

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