Also consider the number of re-purposed passenger cars over the years: sleeping cars to coaches, sleeping cars and coaches to baggage cars, RPO’s to express trailers, etc.
Also Amtrak converted some F40’s by gutting these engines (retaining the cabs for push-pull operation) and making them into baggage cars with roll-up doors.
Do not forget the Monon that made Whole Passenget trains out of Troop Sleepers after WW2 Bought them Cheap and made them look Real Nice for 1/4 of the cost of Buying New if the reports are true.