[racerxpl]

Do you have a sealed system with an expansion tank or do you have a cap on the radiator. Some models had the capped radiator. You might check out your expansion tank cap. It could be that it has become clogged and the pressure gets too high. It is possible the sensor for the guage has gone bad. You might loosen the brass bleeder valve on the engine. It should have no air bubbles come out when you open it. Run the car with that open and see. It is not a simple job to change the head gasket and it is expensive.
Also fill the exkpansion tank all the way up with the car running and see if you get steady air bubbles out of it that way. If so then the head gasket is bad.
I assumed you checked the hoses.