More so the brackets to hold it in. The middle hole below is supposed to hold a bolt that keeps the extender in place. But there are no threads to screw into. Can some post some pics of how it's installed thanks

 

There are threads there. Just start screwing in the bolt. It will grab.
If you go to the Ford owners site and the accessories section. You can download directions for their bed extender. It is real simple. Just insert the plastic grommets into the upper and lower holes, the screw the bed extender into the middle. Should take all of 10 minutes.

 

Seriously there are no threads in there. Here is the bolt ford sold me and the hole close up. I suck my pinky in there almost two inches of space and that's it.

 

try taking off your tail light and putting a nut on the back side of it?

 

Hahahahahahhahha quote of the year. First I was like WTF??? then I reread my post. Oh and I can get to back of the hole when I remove the tails THANKS!

 

Its a self tapping screw, start it and crank it in.

 

glad i could make you smile, hope you got it worked out, use a lock washer or a nylock nut