Here is a link for one to fit 64-66 GMC finding the right one for a 63 will drive you nuts I know it's not out there unless you find a oem part for a 63 that someone may have. Well heck fix it anyway you wish only you will know it's not oem was my point I used the Chevrolet cup and turn signal arm was just a suggestion and so on my 65 it works great..Vernski
http://www.classicparts.com/1963-Tur...fo/53-507A/#.U