You could do it yourself as breakonthru mentions, but if close to Longmont best to just take it to DPA. They will have a tool that fits into the too little holes/slots if the front face of the adapter for loosening/tightening it, so as not to damage the threads, and will probably put a dab of the correct thread-locking compound on there (not too weak, not too permanent) to keep it from loosening.