On an LT1 there is no easy way to do this. You might want to see if there is a fourm dedicated to these cars, or go to camaroz28.com or ls1tech.com and poke around.
I belive the car is ODBI so if someone has LT1 edit or something similar they can monkey around with it. I doubt you will get much of a MPG upgrade, this is nearly a five thousand pound car...