I see you put the new header gaskets in but are the headers hitting the oil pan and not seating on the head? Did you see any dark spots on the old gaskets? You can try to slide a feeler gauge from the bottom and see if it passes the gasket into the header. Or use a small mirror and put under the exhaust ports at the headers with the motor running to see if the mirror fogs up. Some headers hit the oil pan and don't seal 100% I like to use red RTV on mine to make sure they seal. Good luck
