Me thinks you are confused between five windows and split windshields. One piece windshield is a 54 or 55, split windshield is 53 or earlier. Five window indicates the corner glass in the back of the cap and was available on all 47-55 model trucks.
1953 Chevrolet 3600 Fried Green T'mater (Vern) In the Stovebolt Gallery Caution: Political Statement Man who runs in front of car gets tired, man who runs behind car gets exhausted.