What Byrds member served as a guest musician on Rock Salt & Nails
Rock Salt &amp; Nails (album):  It is a pioneering Country rock/Outlaw country album that was recorded in 1969, with guest musicians Gram Parsons, Gene Clark and James Burton. Gene Clark: Harold Eugene "Gene" Clark (November 17, 1944 – May 24, 1991) was an American singer-songwriter and founding member of the folk rock band the Byrds. Gene Clark:  He was the Byrds' principal songwriter between 1964 and early 1966, writing most of the band's best-known originals from this period, including "I'll Feel a Whole Lot Better", "She Don't Care About Time", and "Set You Free This Time".
Gene Clark