How to Remove Cylinder Heads on 2003 Mitsubishi Diamante

My wife drove our 2003 Diamante to class when the water pump broke and the car jumped time. She was able to drive the car into the nearest parking lot and shut off the engine. She mentioned a rotten egg smell and noticed smoke or steam coming from under the passenger side hood near the bottom of the windshield. After several failed start attempts, roadside assistance towed the car back to our house. That's where it's been since the incident.

I removed the timing belt cover, adjusted to TDC, and found the front bank jumped 3 teeth and the back bank jumped one tooth. The tension pulley must have broken, too, because I saw a circular groove burned into to belt cover. The plenum, valve covers, and spark plugs have been removed so far. The passenger tire is off and the vehicle is on jack stands.

I want to check the condition of the valves but I'm not sure on how to remove the cylinder heads. I have basic hand tools and the web to assist me because money is really tight right now. Any help would be more than appreciated. Let me know if there is any other pieces of information that I can provide. Thanks again.