A few years ago I happened to acquire some boxes of "junk" trains which turned out to have some interesting pieces buried underneath, including a postwar Lionel olive drab caboose and olive drab gondola. They were original and complete without significant damage. There was also a 1061 Scout loco needing work, and those items together could have been from an uncatalogued set.
At first glance I wasn't impressed with the caboose. No end railings, that's a serious FRA violation. It's a totally lackluster item except for the fact that the color was uncommon and used for only a few sets.
I "upgraded" my olive drab caboose with a better under-frame with end railings, installed matching trucks with couplers on both ends, installed end ladders and an original Lionel caboose window insert. I was fortunate to have acquired these various spare parts from friends.
So now I have a more acceptably-equipped caboose, but the purist collectors will be mortified that I have modified it from its original "collectible" condition.
Postwar Lionel caboose question - about the under-frames:
Originally the cabooses had a basically flat under-frame, and later they had a domed extrusion where the truck mounts, so the caboose frame and body ride higher. I suspect this was done because the plastic AAR trucks introduced in 1957 needed more clearance for the caboose corner steps. Can someone confirm this?
I've used 'flat' under-frames on some other cabooses with plastic postwar trucks so they ride lower, and trimmed the inside corners of the steps slightly for clearance. They manage O27 curves and the steps aren't so obviously high off the ground.