Exhaust flange gasket

98 Metro 1.0. The exhaust flange gasket is a flat gasket. When I tighten up the flanges so that there is no leakage it moves the pipes over so that the pipe hits the frame and/or the oil pan. It the flanges are tightened so that the pipe misses there is leakage. If I could get a tapered doughnut gasket it would be possible to get a couple of degrees offset. Anyone else have this problem? Any source for a tapered doughnut?

I replaced the whole exhaust on mine and my replacement donut still allowed me to move the pipe without it leaking. Are you sure something is not bent?

I am not sure on anything in regard to the exhaust system on this car. The front pipe w/ the converter is original. The rest has been replaced 3-4 times in 67000 miles. At about 60000 the pipe suddenly wore a hole through the oil pan. The only way I can prevent a repeat is by putting a clamp on the pipe to physically hold it over to the side. No dents or any indication of damage on the pipe. The motor mounts are OK so the engine is not out of position. Everything looks OK with no indication of damage. Even the first time it wore a hole in the pan the exhaust system had been on the car for at least six months. After welding the pan it was worn through again within two weeks. The exhaust system has been the biggest problem with the car.