Robert Glynn Luman (15 April 1937 – 27 December 1978) was an American country and rockabilly singer–songwriter. (Wikipedia)
He is best known for his 1960 crossover hit that made it to the #7 spot on the Billboard Hot 100, Let's Think About Living. How quaint the reference to the fellow with the switchblade knife. It was a tamer time.
Red Cadillac and a Black Moustache
The Bard's version
The Gun. Great period photos.
Gene Vincent's version
And of course Merle Haggard's. "He who travels fastest goes alone."
More satisfying to my mind and ear is Jean Shepard's version. I first heard it in 1965 in Joan Baez's rendition on her Farewell Angelina album.