50jimmy,
My heart goes out to you. The situation you are experiencing is the reason I decided to do a frame off restoration of my truck. The frame for my truck had been damaged. I was too concerned with rust and any other damage that I did not see that it was not sitting straight. It probably did not help that it was sitting on dirt and not pavement when I looked at it. One side was bent down in the front and the whole frame no longer had any torsional strength. There must have been some broken rivets somewhere in the crossmembers. I replaced the center K-member with a new x-member and the frame stiffened up very well.
On another note, if your springs, shackels and all mounting hardware are not in like new condition, it will be difficult to determine the cause of your tweaked frame. I spent many hours under my truck measuring to find the problem and it was very difficult. In the end, I did not find the real problem until I took the truck apart.
Goood luck with your 50.
