I actually thought you were removing it from the car, after rereading you are just removing the hub correct? If so give the end of the half shaft a whack, just make sure it is a rubber mallet. Also you have to get new half shafts nuts, they are not reusable. I assume you have everything disconnected from the hub already? When you re-install the half shaft make sure you have a big enough air impact, the torque of the axel nut is what sets the preload on the wheel bearing.