More on question 3. Here's what I'm aware of, which is by no means an exhaustive disposition list:
-As mentioned, some of the later Pullman cars went to Nashville and operate essentially unrepainted.
-Some of the original St. Louit cars went to VRE in Washington and were refurbished and repainted. A second batch of later Pullmans arrived and operate unrepainted but relettered.
-Additional late Pullman cars went to MARC in Washington to operate the OTHER way out of Union Station, having been relettered and receiving striping on the ends. Neither D.C. operator received cabs that I am aware of.
-Many of the early Pullmans (easily confused with St. Louis cars for the window arrangements) and some cab cars wound up being owned by Midwest Transportation and Devleopment Corp. (see
http://www.cl.ais.net/~dbehr/) These were leased out briefly to Caltrain and--I think--Montreal, but haven't done much since. When I spoke with the guy, he wouldn't say how many he bought, but acknowledged to having scrapped about half of the fleet due to age, deterioration, lack of business, etc.
-Other cars besides MTDC's have probably been scrapped--in particular cab cars (see photos in
http://www.chicagoswitching.com/v4/arti ... ticleid=89)
-A mystery fleet of about a dozen were spotted on the San Diego and Imperial Valley in California about a year ago
-Wisconsin and Southern acquired at least three which they have repainted and operate
-Algoma Central is slated to begin operating several in Sault Ste. Marie - Hearst service, apparently, but I don't know when.
-Union Pacific supposedly retained several for work train service
-At least two different tourist lines have picked some up, but I don't remember who.
Feel free to add to this if anyone knows more--I'm always curious where this fleet disbursed to.
As an aside, the yellow and green cars acquired by Nashville are NOT suburban cars. Those are the former Great Lakes Western, nee Amtrak, originally C&NW intercity cars built in the same shells as the suburban fleet. I haven't been able to figure out what happened to most of that fleet after Amtrak retired them. It appears that the single-level diner with the bilevel roof ended up in a restaurant in Lake Geneva WI, but I never found it personally.
For a variety of reasons, probably having to do with cab signals and other equipment, transit agencies have preferred Metra's trailers to cab cars. Curiously, though, at least some of the old Rock Island cabs had been converted to trailers when brought over to the North Western lines ca. 1980.