Is there a difference between 2wd and 4wd frame other than spring mounts?

[akcheyenne]

I bought a 72 cheyenne over the net and had it shipped to me. My error I know, Now that I have gotten past kicking myself I have found that the frame has been cracked and welded by power steering assembly. I know this is common but would I have worked hard to straighten the body and the frame does not appear to have been welded correctly. I have found a 2wd frame and am wondering if I switch the leaf spring mounts is there anything else that will catch me off guard???