Saying goodbye is never easy, but no one’s ever said it quite the way Glen Campbell has. Following his Alzheimer’s diagnosis in 2011, the country legend made it his mission to muster every last ounce of himself to bid his fans adieu, first with his Goodbye Tour and accompanying documentary I’ll Be Me, and now with his final LP, Adios. With that album due to be released this week, Campbell has given a peek at one of its most personal moments with the biographical “Arkansas Farmboy.”