The Stovebolt Site Forums The Shop Area Interiors how do you attach the "behind the seat cardboard"?

I am redoing my seat in my 57 3100.
I have a vinyl covered "behind the seat cardboard" piece that I want to attach to cover the seat back springs.

But I am not sure how to actually attach it. I think the vendor said to use screws and stainless steel grommets. But I do not see any way of doing that unless you are suppose to screw into the seat back steel tubing.

How did it use to be done back in the 50's?
Was there some type of clip or something?

If it is screwed what is the location of the screws and how many are there?

Does anyone have a good picture they could share showing the setup, locations and number of fasteners?

I know that most trucks never had these as it is the back of teh seat that never gets seen.

In my case I have a big window 57 3100 and you can see the back of the seat and springs on the top (a little) when you look at the truck from the back. So I would like to clean it up a big and install the back cover.

The truck is 54 years old and the springs have gotten a bit rusty. and the batting is not in grate shape but is still there. But it would look better covered. Since vendors sell the cardboard option and some offer to cover it I decided to have one covered when I got my seat covers.

Now I need to figure how to install it.

I think the back cardboards may have only been used on Cameo or possibly Deluxe cab interiors. Or maybe not at all.