Gah!! Old cars!! (steering Qs)

OP you need to be careful what you have and what you buy. Look at your first photo. The stud direction changed between 72 and 73 regardless of sector spline size. Your studs point down, which is the 73/ later style. Like this:

new-jpg.jpg

The 72/ earlier style linkage had the studs reversed, pointing "up" like this

old-jpg.jpg