I am in the process of changing my thermostat at the moment, and have the intake fully off. I could not see any other way of doing it. With the overheating problems you have had, I would be replacing all the small coolant hoses, plus the water pipe o-rings, that are under there at the same time. They will also be cooked, and it is a lot easier to do it all once, rather than having to pull the intake manifold off several times.

PK