73 dart sport, What power steering sector shaft do i have ?????

hey guys i have a 1973 dodge dart sport. My power steering box had so much slop in it it was scary driving it. I just puchased the firm feel power steering box. But they asked me what sector spine shaft i had , i was not sure. I think its the large one but not sure. Does any body know if its the large or the small one??????

Thanks