Many thanks for your comments, David, Rooster, Forrest, Todd & Jerry!
@Jerry: I’m not made up my mind so far - the 70-seat coach would require to change the number & spacing of windows, the 52-seat coach shortening the whole body and the diner/observation would need even a bigger changes of windows’ arrangement.
In later years #9908 was towing two to four heavyweights - maybe I’ll rebuild Aristo-HW to make up this train.
Using the generic Budd-cars to keep the possiblity to interchange with other CBQ-units (have two E8, considering to build the ‘Silver King’, maybe an E-5 or E-7 as well).
Something completely different…UP’s M-23 now got its painted trailer
Regards
Norman