It's been a while since I've been there, but the Shell / Coles Express stations seem to have consistent signage, with the Shell logo on top, and Coles Express below this (I've generally used Shell for amenity=fuel, and Coles Express for the associated convenience store). I looked at the Bathurst Shell/Coles Express today on the way to work, and this is how it is signed. Google images (not a valid source!) show similar signage in Port Macquarie. Hope that helps.