Mopar did a great job designing the magnum's exhaust port then did a piss poor job on the intake ports. You can grind the intakes some to get that pinch cut down. I ground an intake port on a 5302 magnum head and intensionally cut into the pushrod area to see how far is safe (see pics). I cut .129 (5/32") deep before I went through. So it looks like you can take 3/32" (.093) off the restriction and be safe.