Parthery, it didn't work like that at all. It could be an aftermarket previous owner solution, I'm not sure.
Here, you can see the difference in the width of the blades. The new Anco 52-16 blade is on the left; the original blade is on the right. You can see where the Anco blade gets skinny at the attaching point, and that resulted in me having to "engineer" the new attaching point on the Anco blade.
This is how I had to modify the attaching point by using a #6 screw and stainless nuts as spacers. I ended up using an allen head cap screw with a stainless cap nut with some blue loctite rather than a round head bolt and nylock nut mainly for the aesthetics of it. You can also see how the original blade attached to the wiper arm; the original blade was riveted to the same place that I used the bolt/nuts.
Here is the original blade connecting point
This is the completed blade assembly