You should just be able to knock the bottom balljoint loose and pull the axle out of the knuckle. Just remove the cotter pin from the nut and remove the nut. Now, hit the a-arm sharply with a hammer. Don't be afraid to hit it and it will pop off. It takes a quick, sharp blow with the hammer. The arrow, in the picture below, points to the spot where you need to hit the a-arm.