I wanted to change the form’s tags when you create the form elements. I wanted a div around certain element. The form csthl items are located in your [siteroot]\Views\FormBuilder\FieldTemplates
Pick the item you want. You can change it there but better option is to create the same folder structure under Visual Studio project’s view. And add the cshtml file there. Make sure you mark it as a content and to update if newer.
Voila. You are all set.