Those end clips for the center molding go over the windshield molding to cover that gap. If you buy some of the repop ones, you could get them chromed, which would be $$$, assuming you can find a chrome shop.
Another alternative is to get some stainless steel sheet metal and duplicate the clips using that, and polish them up. A simple slot, a slight bend and a radius bend would do the trick.
That's the beauty of having a plain trim level truck. Mine are just painted cab interior color, as is the center trim and windshield molding.
