For the passenger cars, I recently made a list of their replacement trucks. For the smoothside cars, black trucks, the #800041 trucks were out of stock. However, #800104, black Pullman trucks, look identical to me, and work just fine.
#800101, black ACF trucks, are very close, differing only in almost invisible spring details, and I have seen both in pictures of GN passenger cars.
Not surprising, as GN had cars built by both, and I suspect that the trucks didn't always stay with a particular car during shop visits.