Enable/ Disable elements under 'edit' depending on role I want some users to have access to certain items under the 'edit' tab but hide others...

I know you can allow a role to 'edit' or not 'edit' a published node content type but that enables and disables the whole of the edit tab!
As I understand your question, you need the Field Permissions module. From the project page:


  The Field Permissions module allows site administrators to set field-level permissions to edit, view and create fields on any entity.


This will allow you to grant permission for editing certain fields to a specific user role.