[1][2] Throughout his career, Willis traveled and recorded with several musicians, including Conway Twitty, Charlie Rich, Roy Orbison, Jerry Lee Lewis, Billy Lee Riley, Eddie Cash, Johnny Bernero, Narvel Felts, Roland Janes, Barbara Pittman, and the Bill Black Combo.

[10] He collaborated with several other Sun musicians in their songs, including with Jerry Lee Lewis in "I'll Sail My Ship Alone" and "Hang Up My Rock And Roll Shoes,"[11] with Roy Orbison in “I Like Love” and "The Fools' Hall of Fame,"[12] and with Charlie Rich in "Lonely Weekends.

[15] Bill Black's Combo earned a Gold Record for "White Silver Sands" and was listed as Billboard's Most Played Instrumental Group from 1959 to 1962.

[16] The group played its songs "Smokie, Part 2" and “Yogi” in the movie Teenage Millionaire, which also starred Chubby Checker,[17][18] Dion DiMucci, and Jackie Wilson.

[21][10] Occasionally musicians visiting Memphis would sit in during the band's sessions to perform, including Pete Fountain and Al Hirt.

After the death of one of his daughters in 2001, Willis retired in 2005 to Valrico, Florida, making his last performance the next year with Billy Lee Riley and "The Little Green Men" at the Memphis in May music festival.