Complex sentence: In 1966 he became an assistant at the University of Montana in Missoula, then moved to his alma mater at Washington State under Jim Sweeney in 1969, staying in Pullman through the 1975 season.
Split into simpler sentences: In 1966 he became an assistant coach at the University of Montana in Missoula. After two seasons he moved to his alma mater in 1968 as an assistant under head coach Jim Sweeney, and stayed in Pullman through the 1975 season.