98 disco v8 4.0 liter gasoline . My thermostate stuck open , car would not run up to temp , about 1/3 of the way i replaced it 4 days later i smelled antifreeze , i am sure its my intake manifold gasket! theres no cooliant in the oil, none burning out the exaust, small drip in the back of the motor rear of manifold, it runs fine ! what is the best way to replace what should i beware about ! I ask because you chaps are the best with landys! inlightin me! could the thermostate sticking made the intake seal leak.?