I bought a new DG exhaust kit, and it doesn't fit. The pipe is about 3 inches wider at the base, past the first 90 deg turn. The pipe is so wide it hits the frame. Does anyone know if there was a big difference in the engine case between the 350 and 250? Is it possible that i have a 250 case and a 350 cylinder? It's possible the guy sent me the wrong pipe, but i really don't want to buy another to find out and have 2 laying around.