Just bought a 94 Mustang GT with only 67000 miles. When i bought it i knew there was a minor radiator leak, but when you drove it, the leak subsided. Meanwhile...the far left temp gauge would fluctuate from hot to cold. The folks at the shop said that the leak could be controlled with stop leak until a new radiator could be replaced and it pressure checked okay. The temp gauge still fluctuated and the heater worked great and still does. Now, the temp gauge is stuck on H even when the motor is off and the engine is cool. The radiator doesn't leak much and i was thinking a thermostat replacement would fix the gauge issue. Anyone have any thoughts?