I'm not sure what your real question is though?
I'm asking how a guy knows a truck with whatever hitch, frame, spings and axles, motor and transmission, is up to the job of pulling a trailer that weighs a given amount.
When Chevrolet says that '89 K3500 was rated to pull 10,000 pounds what were they measuring?
If I use the GMC 1-ton frame and add pieces as I've described above, how do I know its good for pulling X,000 pounds? Axles? Springs? Frame? Motor/transmission?
My answer would be the weakest link in the chain determines how much I can pull. But since I don't know what the frame is good for, I can't evaluate that part. I can buy a hitch with the rating I need, I can use axles with known rating, but how do I know that my 1-ton frame will handle the load.
