After graduating from Michigan State, Peppler tried playing minor league baseball and became a head football coach at the high school level, winning state championships at both East Lansing High School and Grant High School in Michigan. That success led to an eight-year tenure as an assistant at North Carolina State University beginning in 1954, followed by one year at Wake Forest University in 1962. On January 28, 1963, one month after winning their second straight NFL title, the Green Bay Packers hired Peppler as director of player personnel, where he worked with head coach Vince Lombardi in helping continue a talent pipeline that won three more championships, including their first two Super Bowls.