there should be a check valve in that line between the airbox and the back plate as well
Arrow points towards the Throttle body
Wait for it......wait for it....(BING!)
Oh!..I see now! Thanks guys, and thanks for the link krayzc. I'll bet once I get the check valve in the line from the airbox to the backplate, the midrange and idle might lean up and run smooth. Darn thing is, I just received my order from Central Hobbies for the 75* header and only one check valve.
Got to get another looks like. Thanks again fellas, Mike.