I've gotten the infamous p0420 and after eliminating all other possibilities, have accepted it's time for a new cat. I've got one on order from ZZP as well as a set of spark plug anti foulers to keep the code from coming back, but the bolts from my manifold to the downpipe and cat to the resonator are just slim rusted stumps of their former selves. Before I grind them away, does anybody know what type of bolts they are supposed to be, so I can get one ones to have on hand for the repair?