I just replaced my exhaust manifold, manifold gasket and put in new manifold and flange bolts. I noticed an exhaust leak where the manifold meets the exhaust pipe which is making quite a bit of noise. The flange is pretty rusted. Any advice on what to do next? Should I replace the old flange with a new one? I believe Walker sells new flanges that should fit the truck. I believe the exhaust pipe is 2 inches. Any help is appreciated