why dont you just take the time to gut it out??? If you take it out or gut it disconnect the batterie for like 8 hours then connect it up and rev it to about 500 below the red line. I dont konw about taking the whole cat out though!!!
Shouldn't "mess anything up", but if you remove them, you may find yourself in a "mess" with state pollution laws. If you really don't want them, core um out. No one will know the differance that way.
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Ashes to ashes, dust to dust,
If it wasn't for FORD,
All my tools would rust.