how do i remove the drive clutch off my strimmer?

how do i remove the clutch off my chalenge extreme petrol strimmer SGT26N the pull cord has disengaged from the engine inside, the pull cord mechinisum is situated inside the front housing and it will not drive the engine, I need to remove the housing once i have removed the clutch the clutch has stamped on it 3/8 24mm and a directional arrow.