Since 2000, Swarthmore resident Lawrence Katz has been a guitarist for the Mighty Mighty Bosstones, a group you most likely know for songs they recorded before Katz joined them, such as 1992’s “Where Did You Go?” or 1993’s “Someday I Suppose.” The band’s sound is sometimes punk overlaid with ska horns, sometimes straighter ska but with rock-and-roll guitar solos. This is a story of his musical journey, including how he found Swarthmore.