I see your problem. You have one end of clamp on outside of the windshield. Both ends of the clamp should be on the inside of the windshield, making sure that the rubber spacers are between the clamps and windshield. The 2 clamp ends should come together and almost touch ( depending on how tight you tighten it). The only thing on the outside of the windshield should be the screw and robber grommet with the metal bushing in it. You have to push the metal bushing/sleeve out of the grommet to be able to get the rubber grommet in the windshiel, the slide the metal sleeve back in. Then you can slide the bolt through the windshield and through both end of the clamp. This is when I used needle nose vise grips to compress both ends of the clamp to be able to get the nut started.