Walthers'cars are supposed to be based on 'BUDD designs while ConCor's 85 footers are supposed to be based on ACF designes - accordinnig to them..
I only know of ONE car produced by ConCor that the Santa Fe actually used (Coach).,.
Side by siide the ConCor's LOSE with Talgo trucks & couplers,, and some were shipped with plastic wheels.that would handle 22" curves..
Walther's cars were based on Pullman Standard cars and Budd cars. The Budd cars were the RPO, baggage, and "Pine" 10-6 sleepers. The balance of the cars released as a part of that set were Pullman Standard cars.
As far as the Con Cor cars go, the diner is based on the Pullman Standard built 600 series floorplan, and the dome was based on the Pullman Standard built 500 series floorplan ("Pleasure Dome"). Those cars were it in plastic until Walther's released theirs. As Don pointed out, the Con Cor cars left a lot to be desired with the trucks, no interior, lack of underbody detail, poor window placement/dimensions, etc.
The only cars that ACF built (speaking strictly of sleepers) that was used on the 1951+ Super Chief were 10-6 "Palm" sleepers, and some of the 4-4-2 "Regal" sleepers (the other 4-4-2s were PS). On occasion you may have seen an ACF RPO or baggage car, though.