Well, it's not my primary interest, but I'm a Scot. As a boy in the 60s, I picked up a number of old, old cars in a box-of-trains at a yard sale. Some had wood floors, and thin metal bodies. Until 4 years ago, they all lived in boxes and got carted from attic to attic for 40 years ago. Not one has been thrown away.
I too love bringing these old cars back to life. Tonight, I resurrected an old Mantua hopper and a Crown tank car. Admittedly, these were plastic cars, but they're now equipped with Kadees and running behind modern DCC-equipped engines.
I've got a few old ice-bunker reefers with the thin, sheet-metal bodies and wood floors. The Pabst Blue Ribbon car is on the layout now, parked in front of the icing station awaiting its next load. I think there's an old Borden red-white-and-blue car in a box somewhere, too.
Really, all it takes is a Kadee coupler, spring and draft gear box. If the trucks are in good shape, clean them up and maybe add a bit of oil. You could add some grab-ons to improve the model, but I'm not sure they're worth that much trouble. Instead, run them as "background cars" on your train. And remember how much you loved cars like this when you were a boy.