Hi Aleksandrs,
the story about the IBM 1401 is very interesting. My father used to work on an IBM 1401 in the 1960s. The only museum I know, which does similar work is technikum29 in Germany.
http://www.technikum29.de/en/ As you already know, they have reconstructed the NCR 446 and put them back into working order. They have done the same with an UNIVAC 9400, which is also a mainframe from the 1960s.
http://www.technikum29.de/en/computer/univac9400.shtmAs far as a NCR mainframe is concerned, I haven't seen, that that has been done. But it would be nice, if somebody could find something in that direction.
Best regards Wally (Walter Meyer).