2000 Chevy Cavalier serpentine pully

I tried to get the serpentine pully asembly off my girl friends cavalier and I cant get it. I got the bolt all the way unthreaded but it hits the body of the car and wont come out of its screw hole and it is all the way unthreaded im 100% sure that it is. I was wondering if the engine had to be pulled to do that or if there is a trick to it! Please help me out! I need to get it fixed fast! Thanks nate