Leaking aluminum Mopar valve covers!!!
I always had to notch and bevel the cast aluminum valve covers around the intake ports. You have to look closely to make sure there still isn't a spot that hits metal-to-metal. I've also glued/stacked very firm cork/rubber gaskets from ROL (VS5876HP) to raise them. This was with longer studs and the T-handle hold-downs. It helps to locate them too!