The interior of the cab those years was "champagne". I am in the process of doing my cab interior now, and purchased some of chevy duty's interior cab paint, and I find it a lot darker than I expected "champagne" to be. But I think that 50+ years of sun has bleached any original cab paint I have seen, making the paint appear a lot lighter.
Cab interiors were not maroon, but the upholstery was maroon, along with the cardboard door panels. Maybe that is what they were talking about when they said maroon.