Paul of Guitar Fame is a reference to the legendary musician Paul McCartney. He is best known as a member of the iconic band The Beatles, and for his solo career as a singer-songwriter and multi-instrumentalist. His fame as a guitarist is well-deserved, as he was an influential figure in the development of rock music. The Les in the crossword solution is a reference to Les Paul, another famous guitarist who pioneered the development of the solid-body electric guitar.