In deference to post #6&7, my 31 coupe has a metal tubing which runs from the inside of the firewall fitting, up and through the inside of the metal stanchion, making a 90 degree turn on the top of the windshield. The rubber tubing starts at that point and runs to the wiper. Clamps are attached via the header screws which hold the rubber tubing in place. I also used a rubber grommet around the rubber tubing as it exited the frame to the wiper. This method seals and keeps the rubber tubing in place. Good Luck.