Harold and I have exchanged emails on this in recent days. I am aware of four trucks that appear to have used slotted head screws instead of clutch head type on the windshield assembly . I am uncertain clutch heads were used on the windshield divider bar and “T” brackets but do wonder if not used, why there would have been a change from the rest of the cab sheet metal fasteners. The screws used on Sparky do appear to recess into the holes in the divider bar and “T” brackets a tad better than a clutch head might?