Ya my filters were rather large also had to "modify" the back of the grill insert to open up the airflow and allow them to fit. Only difference i see was i used some 3 inch fuel filler hose to go through the open spots next to the radiator. They were flexible and form fitting to let those pipes move around a little when the engine torques. Never could make hard Y pipes for the inlet of the throttlebody had to stick with the Silcone Y because that motor moves around so much.
A custom intake on these cars really makes the difference in sound and power.