WIW '72 340 'CUDA

I normally would say parts car but being its a 340 4 speed car I would have to personally inspect it before drawing a conclusion. All cars rust differently and its possible the frame rails are good. Floor pans....highly doubt it.
The lack of fender tag and build sheet hurts the value because you cant prove the options it has. However you can prove its a real 340 car so it has that going for it. Check the engine and trans numbers and see if they match the car.
I would at least try to sell it complete before thinking about parting it out. Myself, I like punishment so I would restore it.