Exhaust Gas Recirculation, or EGR system is an emissions reduction system.

What it does:

It reroutes burnt exhaust gases back to the intake air. The effect of the introduction of inert or incombustible gas increases gas mileage by displacing burnable oxygen/fuel withought effecting the air/fuel ratio. It decreases cylinder temperature (less boom, less heat), increases gas mileage (less oxygen, less fuel needed), and reduces the amount of NOx getting into the atmosphere.
The EGR valve is operated via vacuum passed to it from the EGR Solenoid. The computer sends a signal to the solenoid (during part throttle cruise conditions) which send vacuum to the valve, causing it to open at a varying amount.

A negative of the EGR, is that it introduces hot exhaust into the intake. This heats intake air temps, and can heatsoak the intake manifold causing reduced wide open throttle performance.

That is the reason for this mod, where a plate replaces the valve, eliminating intake air mixing with hot exhaust.

What's needed:

EGR block-off plate. (or simply modify the valve to make it inoperative)
EGR gasket, you can see below in the picture, its utilized in many applications. (Fel-Pro 70978)
Chip- the stock chip will set a code at highway speeds if the egr is inoperative.
Vacuum Nipple - to block the vacuum source to the egr. Can use something as simple as a screw in the vac line if your cheap.

How To:

This is illegal-I'd only recommend it to race-only vehicles. (standard disclaimer, don't blame me if the egr police come after you.)
Simple process, remove the vacuum elbow from the valve.
Remove egr valve, the bottom bolt is a PITA, I used a closed ended wrench reaching around the back of the valve to loosen it.
Optional: Remove the 2 vac lines shown below, one from the solenoid to the valve, the other from the vac harness to the solenoid.
(if you want to you can just block off the vacuum line with a nipple or screw at any point to prevent a vacuum leak) I blocked off the line where it meets the main harness above the passenger valve cover with a nipple over the end of the "T" that fed it.
Optional: Remove the Solenoid. 2 screws hold it onto the bracket that holds the solenoid and coil. Remove those 2 screws and unplug it from the wire harness. Tuck the connector away, and your done.