Chris. i dont know about you, but i didnt have to wear a mask or nor did i taste any metal. i was using a straight air die grinder with carbide bits with the regulator turned down and dremel tool.
what did you use?
gee, i smoothed the crap out of them. i sanded the ports with fine paper about 10 times each cylinder. i can even drag a razor blade across the port without it catching. hey its all i had. i took me 5 hours per head. man it is tuff to get in there!