Well, for future reference, the cat is welded on. I cut off the old one and can't find anywhere that has the direct fit cat so I'm gonna try the universal one. If this doesn't do it maybe the muffler is clogged so I'll try to blow that out with the air hose. Now, if that isn't the problem and I just wasted all this time and money on the cat, can anyone think of why it would shake so bad and have no power? Gas pedal floored for a block and I got up to 30MPH.