The design team at CLC has studied the actuating rod lengths and concluded that the 13-1/4″ & 19-1/4″ spec is too close for comfort. 13-3/8″ and 19-1/2″ for upper and lower, respectively, is better. Or rather, better that you cut the rods a little long and then trim if necessary. Too long is a problem, too, but it’s easier to trim a steel rod than to add length!
We’ll be sending around an official Technical Bulletin on this.