I am using the rough edge to drill forward and the smooth edge to drill in reverse. That bolt just stares back in defiance. I was able to remove two of the bolts using a hex socket head and a torque socket wrench. I also tried an air impact wrench without success.
All of the suggestions were useful.I tried everything and eventually pulled the rotor off the crank and found a nearby shop to put it in the vise bench. The guy then went through each of the suggestions (except for the welding, we got the bolts free). The last bolt only came out after using an impact chisel to inch it CCW. I've up-voted the suggestions and picked the answer that helped me the most. Just wanted to say thanks to all the posters.