Complex sentence: In Kes he played an English school-teacher-a job which (like fellow Kes actor Brian Glover and its writer Barry Hines) he had had in real life, having taught art at Manchester Road Secondary Modern school in Leigh, Lancashire.
Split into simpler sentences: In Kes he played an English school-teacher, a job which (like fellow Kes actor Brian Glover and its writer Barry Hines) he had had in real life. Colin Welland taught'art' at Manchester Road Secondary Modern school in Leigh, Lancashire.