What is the easiest way to get off of 6 1/2mg xanax/day without withdrawl?

Switch and quit. Switch to equivalent dose of long acting benzo like Valium or Klonopin (clonazepam) and then taper gradually as tolerated -- will take weeks. Your dr. Must plan and supervise the details. You should also plan on getting out patient addiction, therapy, 12 step meetings etc.