Mainline Modeler ran 6 articles on the ARA 1932 cars:
October 1992
November 1992
January 1993
April 1993
December 1993
October 1997
SAL, L&A, and NC&StL were the big buyers, Nacionales de Mexico was the 4th largest buyer. A number of RRs ordered lesser numbers, some only got 1.
One of the articles says the ARA 32 design was the most significant design ever and the 1st steel boxcar to be accepted by the RRs as a "standard". A follow up article says there were more models bought that didn't adhere to the original drawing than did!!!
Seaboards cars were built in the Portsmouth shops from kits supplied by Pullman.
There are so many variations I don't see how a model can be built to cover every RR. Roofs, ends, doors, even underframes were swapped or even rebuilt later using newer technological designs.
The writer blames the "times" as the reason the car didn't catch on. In 1929 111,218 cars were ordered, after the stock market crash, only 1,968 cars were ordered in 1933.