I have a friend who has a problem with the spare tire tray, it's a
long story why/how this occurred, but the captive nut that takes the
bolt that secures the tire tray had disappeared.

I'm guessing it was a nut tack welded inside the box section of frame,
but not sure. This diagram shows something different than I imagined,
#10, http://tinyurl.com/3qasgbx.

Anyone know for sure what is going up there in the frame?

alistair