I would like to know what "XM-ID" means on the sides of a B.A.R. Red, White and Blue, 1954 box car.
I know the "Mechanical Designation" for 'X' is 'Box Car' and 'M' is 'General Service,' but what does the added letters: 'ID' stand for?
Can, anyone please inform me.
Thank you,
RJL