Been trying to find the two eye bolts (OEM or a commercial substitute) that attach the ends of the troop seat board backs to the vertical supports, and provide anchor points for the cargo safety strap, but with no luck. The mfr. part no. is CC-990968 according to the photo (Fig. 216) on page 412 of TM 9-8031-2 (13-Mar-1953), but it doesn't appear in the parts catalogue ORD 9 SNL G-741 (21-Jan-1954), in either section 1810 or in the numerical index by manufacturer part number in the back.
It's probably a 5/16-18 x 1-1/4", coarse thread, shouldered, steel, forged eye bolt (i.e. the "eye" is
not made by wrapping the un-threaded bolt shank around in a circle like a question mark), but the problem I'm having is finding one in that thread size with a large enough eye to accommodate the safety strap snap hooks, which are substantial. I'm guessing that the minimum I. D. of the eye would have to be 1".
The eye bolt is item "B" in the image below:

“When a long train of abuses and usurpations, pursuing invariably the same Object evinces a design to reduce them under absolute Despotism, IT IS THEIR RIGHT, IT IS THEIR DUTY, TO THROW OFF SUCH GOVERNMENT...” -Declaration of Independence, 1776