I'm guessing it was stapled from the backside and you can't figure out how to hold it while you attach it to the face frame. I don't think a suction cup would hold on the wood grain. I would drill a tiny hole near each end of the panel and thread a fine wire through the front of one side, across the back and out through the front of the other side. Put a few dabs of hot glue in strategic places and hold the wire in your hands and pull the panel towards you while the glue cools. A wax pencil would disguise the holes.