I am running an RPM Performer on a 440 with a Proform carb in a 71 Chally with the Rallye hood. The air cleaner has about a 1.5" drop base on it. I have only enough room for a hex nut to hold down the air filter top or I touch the bottom of the hood and I do not have any insulation under there. (I know, it's not a Cuda)