I recently purchased the "large flat washers and wingnuts" that are supposed to hold down the rear of the hardtop on a 1969 (the rear fasteners, not the ones on the sides). The catalog states the parts are for '63 to '75. Ummmm, I don't think so - the flat washers and wing nuts are 3/16", and the hardtop bolts (studs) on the rear for '68 and '69 cars are 3/8" - not even close. The flat washers and wing nuts would fit the carriage head bolts for midyear hardtops, but not Shark hardtops. It appears that several, if not all current supplier catalogs list these incorrect parts - does anyone know why this is listed incorrectly and how to get the correct parts (I know that I can simply go to the hardware store - I am really asking if anyone else has experienced this issue)? Additionally, why do current catalogs list wing nuts, when midyear AIMs show hex nuts (and Chevrolet supplied hex nut wrenches) with hardtops? Is it simply to make installation easier?