Having spent a large amount of time riding Harriman coaches to and from school in California, I can state, and not be refuted, that the difference between the ride of a Harriman coach and a boxcar was at best: not noticeable; at worst: I would take the most beat up bad order boxcar any day.
I believe George Hollwedel (georgeloop@austin.rr.com) is planning a run of these using Intermountain. These will be as close to prototype as you can get out of the box since George has IMRC mix & match components from various box cars.
Ok, I won't refute you but I do think using a chopped down observation car painted in a dark grey would look really cool at the end of a long black train. That said, feel free to refute it.
IIRC, the black overnights were introduced in the '40's and the silver ones in the '50's. The silver steel caboose was painted as such to follow the TOFC's introduced in 1953 as was previously stated. I currently have 12 of the black ones and five of the silver ones. I would be interested in a special run although since I run them as a through block it doesn't make a difference to me if they all have the same number. Currently I have four different road numbers. I probably wouldn't need more than eight additional cars as 20 would be all I'd run at any given time.
Randy: Welcome to Trainboard. I might contact George and place an order for his SP overnight boxcars. I'm very happy with the run of ATSF 40' boxcars that he did. Stay cool and run steam.....