I have to replace the cats on my 96 avant (198k miles), because of a offroad incident, Ha! it's not a truck. Well the cat material inside one of them has broke loose My plan is to replace both with welded type universal cats to keep things in balance. My problem is that the bolts that connect the pipe to the exhaust manifold look unremovable after 198000 miles and i don't want to even try. Has anyone cut the pipe just before the cats and used clamps to secure them together? I was even thinking of using refractory cement and clamps. It would be difficult to completely weld the pipe once it is up under the car.
Thanks