Thanks for all the really specific replies. I'm comfortable with doing the X28A in SK, probably well-weathered, if I decide to do it at all. I'm also working on an X26C, an X29B and an X29D, all F&C. (I like to do some similar cars at once, which is a small labor-saving advantage at least with regard to research and assembly technique.) And I have enough decals I should be able to make some good choices when I'm at the lettering stage.
My Westerfield 1/59 ORER shows 2913 X28A. I have a hard copy ORER from 1961 but it's at my other house so I can't check it. I'm really interested in the precipitous decline in the numbers of X28A after 1958 as shown in the prr.railfan.net page, so I was wondering if large numbers of these cars were being condemned or at least being gathered for scrapping rather than being in free interchange during this time.
Ron Merrick