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The aftermarket drip rail moldings are junk if you ask me and if you don't wont to drill holes in your cab you could always install a set of these http://www.classictruck.com/product/1973_1987_Window_vent_shades_WVS73/1973-80_Trucks_Window_Moulding_Trim_and_Frames_Window_Vent_Shades