I would first find a friend, it's a two man job.
First remove the louvers from the drip pans and metal screen. Don't loose the screws or the washers. Take the washers and goto your local hardware store. Find a rubber gromet/washer that has the same hole size as the metal washer but is wider in width. Then grab a couple metal washers the same size as the ones that came from the louvers.
Remove the drip pans, put the screws through the screens and add the washers. Have your friend hold the louver and screen together as you retighten the screws.
That's how I did mine, and they've been there for the past 3 years. Been down the dragstrip multiple times, 100mph+ trips down the interstate and multiple times through the automatic carwash.