Just below Montana, on Harrison.
Look up Habig's on Google, and you'll find reference to a Habig's Restaurant, just up the road at Harrison and Urwiller. A closer look shows there's just a parking lot there now. Google "Habig's Drugs", and you'll find other pictures of this same ghost sign on Flickr.
But, the Habig's name lives on in painting and drywall, apparently.