clamp it in the vise with a rag or something around it that wont let the vise mar the side. Also don't clamp it any tighter than you need to to keep from smashing the slide. Other than that, have a bit of care and hammer away. I dinged up my front sight a slight bit, but not badly by any means. I also had a punch that was a little larger than I would have wished. You should be fine if you have a set. My rear one drove out easy, the front took a bit of smacking.