I got this info from http://www.tccoa.com .
This for anyone who wants to get rid of their cats and does not want their check engine light to come on. There is a special device called a MIL Eliminator that you can get at www.dallasmustang.com ($60 + S&H), that will reroute the signal correctly to the computer without having the OBDII sensors in.
The device just plugs into the back of the rear O2 sensors and they send a signal that tells the computer that everything is ok, just as the O2 sensors would if the cats were there. But just in case you do not want to pay for them, you can build it yourself with parts from RadioShack.

Disclaimer: This is for educational purposes only.


Here is the link to the pic: http://server3002.freeyellow.com/jac...eliminator.jpg

Here is the diagram:

 

 

We have emissions testing here. You also would not be able to legally sell the vehicle until the emissions were put back on.

 

And even if you did happen to sell the truck, if the owner found out that there are no emissions equipment on it, you are held liable. This is especially true if you're the first owner - easy to prove that you had it done.

The Mustang's and Camaro's are way easier in that their are off-road pipes you can buy and they can be swapped in and out fairly easily.

 

That's why I still have the stock H pipe from my 86 GT. I added a BBK H pipe with only two cats. Really helped the exhaust, but never did have it tested. I traded it before it's time was due. Anyway, if "they" ever come back to me, I'll have the stock unit to give them.

 

Ive had my cats off for 6 months now, and the check engine light is still off..