You'll probably go over the head a second time once you get the feel for it. Visually inspect every port to figure out which one you should/can use as a bench mark and match the other ports to that. Remember that the more material you take out of the mouths of the ports will change the heads' characteristics from torque to higher rpm flow. If you're not going to go for oversize valves, don't go crazy on it. The trickiest part will be the valve bowls and the transitions behind them. Keep us posted with your progress!