After Sound Hole, Colla was enlisted as sax man/arranger with Sly and the Family Stone, recording and touring with Sly for a few years. In the late 1970s, Sound Hole and Clover alumni merged to form a new group, the American Express, which later became known as Huey Lewis and the News. For the News, Colla became saxophonist, rhythm guitarist, backing singer and songwriter.
Following his time with Sound Hole, Colla joined Sly and the Family Stone as a sax player, recording and touring for several years. In the late 1970s, alumni from Sound Hole and Clover united to create American Express, which later became Huey Lewis and the News. For this new group, Colla took on roles of saxophonist, rhythm guitarist, backing vocalist, and songwriter.