You'd be better off to leave them alone, it has been proven that that is a low pressure area and opening those up will actually try to pull air out of the engine at certain speeds instead of push air in like most people think. Hood scoops need to be real high or at the leading edge of the hood or straight on in the front grill or bumper area or at the windshield base to do anything.
This was researched a lot in the late 60's and early 70's with all the funky hood scoops they had back then and non of them worked except the ones with the scoops at the front of the hoods, a few cars that using huge ducting hoses from the front of the car and cowl induction hoods.