Unfortunately the experiment didn't go well and while salvageable, I still need to figure out how to handle the transfer caboose flatcar body. It has admittedly far fewer decals I'd have to remake. I may try to do the metal bracing without the hot water, assuming the urethane lets me straighten it without much fuss. Have been depressed about the whole thing and have ignored this for a few days to do other things before finally coming here to post about it.
I admittedly probably made the water too hot (~180 degrees) and left it in there too long, it actually softened too much of the carbody and the way I originally had it mounted caused some of the carbody sides to bow, so I took an hour to fix those mistakes slowly, but I was able to mostly save it. I unfortunately think I will need to redo the paint and decals...as I'm not sure there is a way to remove the white haze. It only subsides when I put more water on it, lol. It was painted with acrylics and covered in layers of lacquer for the decals, and now you can clearly see where the decals are. Not the end of the world as the paint scheme is admittedly far too old for my era. Some of the styrene beams on the bottom curled up, but those are easily replaceable. The carbody itself kinda bows laterally a little bit, but I think I may be able to fix that if I glue in the steel weight back into the pocket. At this point I have nothing to lose but time.
Keith Wiseman never got back to me.
Warning of not what to do...don't dunk the whole car underside down or the good part will also bow...
This car also survived several maddening thoughts of giving up and smashing it against the floor after the carbody bowed.
Some Photos of the nearly deceased after an hour or two of selective dunking in hot water and my hands reshaping the sides back to where they needed to be:
how I ended up having to hold it in the water to keep the carbody from bowing under the clamps:
not perfect, but better than before and pliable enough to attempt to put some brass rod under it to straighten it out:
) the floor is 1/32" too wide for the body and I do not have the capability to shave off 1/64" evenly from each side. Oddly, the floor's length is spot-on. It was put back in the box with a pair of good trucks (I had put them in the kit box before I noticed the floor's problem), now I have to find the kit and extract the trucks before I unload the kit. Probably on the free table at a show. 
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