Watch Willie Nelson and Billy Joe Shaver Bring Outlaw Spirit to 'Letterman'

Willie Nelson and Billy Joe Shaver stopped by The Late Show with David Letterman last night, bringing with them more than 95 combined years of renegade attitude and trend-bucking country music. Backed by a lean band cobbled together from Shaver and Nelson’s touring outfits, included harmonica wiz Mickey Raphael, the two traded……