its a complicated story, search freshalloy for the whole explanation. automatic obd1 cars had 2 cats, and somehow we ended up with the cat being part of the exhaust manifold and the dummy cat is just there. i dont remember the whole thing.

hell an impact gun couldnt get my shit off on last car , but it was the shops fault for using air tools to torque down the nut, and overtightening causing the threads to cross and heat and it was like one piece. impact would be best bet before relying on mr hacksaw. but id rather plasma or hacksaw it cuz u might as well use new bolts anyways.