Hi um, there are more than 1 series that uses square/rectangle shafting. The easiest way to determine if it's 35 series, is measure cap size of u-joint. If it's 1-1/4" , with old school pinch snap rings and not with holes , and square profile you are on the right track. I use a book that has them in order, and check more than one measurement to be sure. 35R is indeed quite common regardless