I checked the thermostat, and it seems to be opening ok. The cap I'm not sure on. The engine was in the 180 area when i loosened it to the pressure release notch, and it didnt seem to have pressure behind it. As for a plugged radiator, pump or gasket, I havent really gotten to that yet. The more i think about it, the placement of that tranny cooler is probably blocking a signifigant portion of airflow. Also, if you've seen my other thread you may know i have a possible retarded timing issue, which may be causing some of this.