are they the stock size for the stock lower? i used the stock gasket for my windsor jr heads which have way bigger ports than stock heads and with my gt40 intake (same lower as yours) all i did was take a dremel and enlarged the gasket ports to alighn right with my heads and intake ports because they were way too small. If in doubt just lign the gasket up with ur intake and see if u need to to enlarge it or or get a bigger gasket which is what i should have done but i had no time so i just enlarged it myself