Pretty Boy Floyd
For the 14th single, Gram Parsons was now clearly exerting a massive influence in the band. But the man with the plan was Chris Hillman. Hillman was firmly ensconced as a primary songwriter in the band and it was he who began pushing the country sound and many critical personnel changes, including using Clarence White as a studio musician and bringing in Gram Parsons to replace David Crosby. Hillman gets songwriting credit for the A-Side, I Am A Pilgrim (Though we agree with the commenter below, it's a traditional song that predates the Byrds). For the Flip-Side Gram Parsons pushed the Woody Guthrie number, Pretty Boy Floyd. Because of contractual issues, Gram Parsons could not sing the lead, leaving Roger McGuinn to more than ably handle the duties. John Hartford plays banjo on the number. I'm unsure of who plays the fiddle and the mandolin.
Drug Store Truck Drivin' Man