I have a 2003 trailblazer with the inline six. The cat plugged and I'm looking for cheap solutions. Plan A is to get a $100 free flowing cat from summit racing and plan B is to cut out the cat and replace it with a piece of pipe. Has anyone tried either of these? If I get a free flowing cat will I need spacers for the o2 sensor? Can I run just a piece of pipe with a space for the o2 sensor or will I run into idling problems and loss of torque?