one option you might want to consider (anyone else jump in here) is to go to your home improvement store in the plumming section, and find ABS plastic cement. Use that to glue your broken piece back on. ABS cement is ABS suspended and liquified plastic (which I believe most dash and plastic components are made of) that will actually liquify and bond both pieces your are trying to reconnect.
Anyway, that's what I would do. It's used by car specialists in a lot of plastic fabrication.