He attended Huron University in South Dakota, starring as a running back from 1956 to 1959 (as well as being a Dean's List honours student.) A First Team NAIA All-America in 1959, set NAIA career records with 394 points scored and over 4,000 rushing yards.
Henley was drafted in 1960 by the NFL's Green Bay Packers in the 15th round (173rd overall), but chose to head to Canada, and the Hamilton Tiger-Cats. This was an excellent decision, as he embarked on a 16 year career (1960 to 1975) of CFL greatness. In his early Tiger-Cat career, he was used mostly as a defensive back with a unique tackling style which relied on his skill in taking down players with body angle and leverage rather than brute force. In his later years with the Tiger-Cats, he played more as a receiver when it became obvious to everyone, coaches, players and fans alike, that he was a superlative offensive player.
As a defensive back he intercepted 59 passes for 916 yards and 5 touchdowns, and was selected as an All Star nine times. An excellent two-way player, as a wide receiver he was an All Star for the 10th time in 1972. He also won the CFL's Most Outstanding Player Award that year in which the Tiger-Cats won the Grey Cup at their home field, Ivor Wynne Stadium in Hamilton, Ontario. No one who saw him will ever forget his playing style.