If you're not going to be lowering your windshield, I wouldn't use any adhesive on it.

But if you routinely lower your windshield, it's kind of a PITA to have to store it and then align it every time you raise the windshield again. If that's the case, I'd use silicone or contact cement to fix it to the cowl. Wouldn't take a whole lot -- just enough so that it stays in place when you lower the windshield.

1977 CJ-7, fiberglass body, AMC 360 w/ headers, DUI ignition, Edelbrock intake and Holley 4150 carb, TF999, Dana 300, 4.56 gears lockers, York air comp, 4" susp lift, 2" body lift, BFG 35" M-T tires, Megashifter, AGR pump & box, REP8000 winch.