A friend is willing to almost give me a 2008 Pilot with a broken timing belt. I have swapped a engine in a Murano before, and I don't really want to undertake that size job again on this vehicle...on this Pilot, should I assume both heads need replaced, and can they be replace with the engine in the car? I have done this in a Accord before, and it was not bad at all, but that was only one head. I think replacing valves means pulling the head, which means having it planed, etc, which is why I would look for rebuilt heads if they are available and save the expense of doing that work. Thanks!