To remove the half shaft, you have to park the car on a flat surface. Lift the car front with a car jack and loosen the nuts. Loosen the bolts , remove the rotor and the brake pads from the caliper. Place a drain pan as you remove the axle shaft and slide it out to remove it. However, you need to do it with a qualified mechanic. See http://www.ehow.com/how_7873508_remove-half-shaft.html for the procedure.