Wow! Thanks for taking all the pictures! Mine's similar, but not exactly the same as yours. I have one curved clevis fork and one straight one, and both are deeper than yours, which allows for more adjustment.
In one of your pictures there are springs laying next to the center joint. Is that where they hook on? I don't have any springs in the middle of mine. Well, at least there weren't any there when I got the truck. Where do the springs attach?