Wanted you guys to see what I tried yesterday....was installing a trailer hitch on one of our cars, it's a unit-body car, had to drill a pair of 1/2 inch holes in the underside where the body is boxed in, the holes had to be accessed from the openings at the rear, and you had to somehow install a half-inch grade 5 carriage bolt and a rectangular backing sleeve in the drilled holes about a FOOT from the end of the openings in the rear of the boxed in section.
The instructions that came with the hitch said to "fishwire" the hardware assemblies into place. DUH.
What I did, shown for illustration here, the parts are not to scale. First, I used hot melt glue to make the bolts/sleeves one solid assembly. Then I tied dental floss to the assemblies, in case I needed to pull them out of the boxed area, if they came out of my claw pick up tool. Well, I didn't need to pull them out, by having the hardware glued together to keep the two parts together, it took less than 20 seconds to seat each one using the pick up tool to get them in the holes I had drilled. For those without such a pick up tool, you could cut a long strip of stiff cardboard, cut a small hole in it, then push the bolt end thru it and use the cardboard to seat the assembly...then pull the cardboard back out.
If this tip helps just one person with such a situation, I consider passing it along worthwhile.