Dee you got some great fish there! First, is this fillet with skin on one side? If so, I put a piece of foil on grill, no oiling foil. Put your fillets on foil that you have lightly oiled and seasoned to your liking, and from there I do the push test for doneness. You don't want your finger to feel the fish is mushy nor firm, somewhere in between. The nice part of the foil, when serving, you use a very thin spatula, and wiggle a bit and skin stays on foil for easy clean-up and takes that burden from the table.