Just because a body style changes, doesn't mean that the cowl changes. The best way to know is to look at the dashboard. If it looks similar, then it usually uses the same windshield. Since redesigning windshields and cowls is such an expensive job, and most consumers never notice the difference, the auto manufacturers tended to use the same cowl for many years. An example would be the 1957 Chrysler products used the same cowl and windshield till 1965, when it changed. The 1959 Cadillac Commercial Chassis cowl, windshield, and dash went through the 1964 model year if I remember, before it was changed, even though they changed the standard production car cowl and windshield in 1961. Usually there are drastic changes, so it should be relatively easy to tell when the change was made by looking at pictures of the cars.
