Have you looked at the subframe yourself? I would, if only to make certain that you're getting good information. Do you live in an area of the country where roads are salted? On one of the coasts?
It's not a job for an amateur. The engine and transmission assembly will have to be supported while the subframe is dropped. Lots of things are attached to the subframe that will have to be disconnected and/or supported. All the fasteners will be corroded. After it's replaced the car will need a wheel alignment.
Only you can know if you're up to the task.