We do not recommend replacing your own windshield, but this is how we do it!
1.) Ensure the new windshield is the proper one for the vehicle. Look it over and make sure there are no scratches or chip.
2.) Remove all trim around windshield, the wipers and cowling exposing all edges of glass. (Be careful not to break any clips that hold the cowling down)
3.) Cut the windshield out. There are many tools for doing this.
4.) Wipe off all Debris then trim the old urethane down to between 1mm to 2mm.
5.) Prep the new Windshield. Install new molding Spray with glass cleaner and Scrub the area the urethane will be with a scotch brite, wipe it down with a paper towl. Be sure it is completely dry, and prep the area the urethane will be with glass prep. Do not install new glass for at least 6 minutes. If the new windshield has any plastic or rubber attached to it you will need to prep that with the appropriate prep as well.
6.) Prime the pinchweld. (There is a open life of 2 weeks for primer so check the date you opened) During the cut out of the windshield and urethane there were probably scratches made. To ensure they do not turn to rust prime them. If rust is present, sand it down to bear metal and prime then wait for 2 minutes and prime again. Wait for 2 minutes before laying urethane.
7.) Make sure there is no dirt/debris where the urethane is to be. Lay the bead of urethane to the height of the roof line. Smooth the butts together.
8.) Set new windshield in place. Wear rubber gloves to ensure you do not contaminate the windshield ( finger grease can make windshield not adhere properly.). and push around the entire windshield glue line.
9.) Re install cowling wipers and mirror.This is how we do it. Not prepping the windshield, or wearing rubber gloves will cause a windshield leak. Not priming scratches, will cause rust. I highly recommend having a professional install your windshield. Otherwise you could not only get rained on, but could be putting your life at risk in the event of an accident!