Keep it simple. I put a LITTLE olive oil on it and cover the top with thinly sliced lemon.
I cook mine on a sheet of foil, makes getting it off the grill a snap and the skin usually sticks to the foil. The meat will separate from the skin with next to no effort.
I assume you are talking fillet. If whole, can't help you.
Brinkmann Smoke 'N Pit Deluxe - ready to get rid of this
Webber Kettle - complete with flavor dent in the lid, under the handle. This one needs to go.
Bradley 4 rack Puck Pusher