Because of the rounded arm swing in the one plane swing the finish features a flatter finish position with your hands lower and further from your head.
Make a rehearsal swing behind the ball; take your grip and then step in with your right foot and bow into the ball with your hips. For a one plane swing it is imperative that you are bent over sufficiently at the hips.
There are four common reasons for why golfers hook the ball, find out which one applies to you and how to fix it