You would be surprised how easy the frame rails can be replaced using a donor car. There are plenty of identical structures as late as 76 models still solid as a rock. You may need to drill a hole or two for bumper braces.
You can bet someone will.
Oh I know, My friend told me that he could do the job in a weekend or two, however I do not have enough space to do it, nor am I willing to drop 6500 on a car with a bad frame. If the car's body/interior was in better shape I would have considered it but with the tranny and oil leaks and multiple other spots of cancer with the potential of major hidden rust damage the car is worth no more than 3 grand to me.