For about 2 years I have used an K&N Air Filter that fits into the Stock Fedaral Air Filter Housing and have not found any grit behind the Filter Element.
However, I am in the process of installing a othe alternative. Using a Fram WA8039 Washable Air Filter (washes in 4 ounces of Dish Soap in water).
The Intake and Air Filter mounting are taken care of but I have I cannot settle on what to do concerning the Breather and the project got more involved when I decided to pull of my Manifolds and Clean them.
Below is a pic of it mounted on the Engine without the Breather Tubing going into it.
Also in another thread I disproved the "Hot Air Intake" theory. The only time the under the hood temp rises much above the outside them is when you are stopped and idling.
I also put this same Air Filter on my Diesel Volvo.
I got one a Walmart for $22 and the other on Amazon that cost more. I could not find any local and the Walmart I bought the original at has no more of them
From a Question I ask
http://www.peachparts.com/shopforum/showthread.php?t=212563