You might look into getting new washers for the valve covers. They are a steel/rubber washer combo. Mine were very dry and cracked. I would also go ahead and get new injector o rings. If money is no object so far, get a fuel pressure regulator, if you haven't replaced it already. These are all pieces you are going to remove anyway, may as well fix it while you're in there! Get some Brake cleaner too. While I had mine All apart, I cleaned the plenum out real well too. After cleaning with the brake cleaner, I soaked all the baffles with seafoam deep creep to lube it all up, and to loosen any carbon that may have been missed. Your valve cover kit should come with new spark plug hole gaskets too. Can't see your post, I would replace thermostat also while you're there. I also sprayed and clearcoqted my covers while they were out.
Good luck!