NOTICE:
If your area requires smog testing, do NOT do this to your car!

Remove the catpipes from the midpipes and headers/downpipes.  I dropped the entire exhaust system, since I was replacing the catback with an aftermarket anyway.  You don't need to remove the entire exhaust to do this though, just the catpipes.

Step 1 - Preparation

Once you have the catpipe free from the midpipe, mount it in the vise securely.  Make sure you give yourself plenty of room to work  Looking into the cat, you'll see a honeycomb-looking mesh.  That's the stuff you'll be knocking out of there.  It consists of ceramic, coated in hell knows what else...  I strongly recommend wearing a dust mask while doing this.  The process creates a lot of dust, and something tells me it's not too healthy to breathe it.

STEP 2 : Breaking the catalyst material apart

This is really easy to do....  The ceramic material is very brittle, and will crumble rather easy.  Place the long screwdriver into the cat, close to center, then strike the handle until you drive it into the material several inches.

Twist and wiggle the handle until it breaks loose, and then pull it out.  Move the tip an inch or two away from the first hole you made, and drive it in with the hammer again.

Keep doing that until you've got a big mess of loose ceramic material....

Periodically remove the cat from the vise and dump the loose material into a bucket or trash can.

STEP 2 : Removing the 'Brillo Pad'

Once you get through an inch or so of the ceramic, you will run into some wire mesh.  It looks like a Brillo Pad to me, so we'll just call it that...  This material is in place to prevent the ceramic material from rattling and coming into direct contact with the cat housing.  There are 2 doughnut rings (one at each end of the ceramic mesh), and one large one in the middle.

When you chisel your way down to these, simply snag them with the screw driver, or use some long needle nose pliers and pull them out.  Make sure you remove all three of them.  If you don't, they can blow back into your resonators or mufflers and clog them up.

The doughnut mesh:

The larger mesh which wraps around the ceramic:

Making progress!!

Step 3 - Finishing

When you get through all the ceramic, you'll come across the third and final 'Brillo Pad'.  Remove that and all remaining ceramic chunks.  Take an air compressor and blow any remaining dust out of the pipe.  You'll have a nice bucket full of crusty crap that came out of the cat.

I recommend disposing of this stuff in a small plastic bag (a Walmart sack works great) and then just putting it in the garbage.  If you leave this stuff loose (especially where moving air can get to it), it will make a dusty mess all over your garage!

When you're all done, you should look into your cat and see this:

That's it!!  Repeat the process to the other cat, and shazam!  You'll have gutted cats!

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