Need correct Pitman arm

A couple of quick questions; First, is there such thing as a large spline (1.25~) opening pitman arm that comes with a nut pointing up (67-72) configuration, as opposed to nut pointing down, (73+style)? I purchased a reman box from NAPA part #31-1036, and my Pitman arm with a spline opening of ~1.1, is to small. Issues I keep running into is that the previous owner of the car had installed a 67 front clip on my 69 barracuda so i have the funky Idler arm. I really don't want to uninstall the steering box with the large spline output shaft. Second question, is it likely that i will have to change out the K Frame/linkage setup in order to get the large diameter output shaft on the steering box to work?